
drop back
at the drop of a hat
[Middle English droppe, from Old English dropa.]
volume Essentially the smallest amount of liquid that can occur naturally in near-spherical form. It is usually stylized in pointed pear-shaped form, the shape it tends to have as it breaks free from some surface holding it by surface tension, hence its smallness depending on gravitational circumstances. Modern research indicates that the smallest feasible three-dimensional drop or droplet of pure water is of 6 molecules hence a volume of about 18 zeptolitres, = 18 zL = 18 × 10-21 L.
Direct marketing: direct-mail promotion entering the direct-mail system; also called mail date. The drop date is usually planned to coincide with a buying season such as Christmas that has produced good results on prior mailings.
Fulfillment: record to be removed from a computer file. See also delete.
noun
verb
phrasal verb - drop by
phrasal verb - drop in
phrasal verb - drop off
1.
Fall asleep, as in When I looked at Grandma, she had dropped off. [Early 1800s]
2.
Decrease; also, become less frequent. For example, Sales have dropped off markedly, or Over the year her visits dropped off. [Early 1800s]
3.
Deliver, unload, as in Bill dropped off the package at the office.
4.
Die, as in He is so ill he could drop off any time. [Early 1800s]
Definition: decrease
Antonyms: increase, rise
n
Definition: steep decline; hole
Antonyms: incline, mound, mountain, rise
v
Definition: abandon; ignore
Antonyms: continue, do, mount, pursue, take up
v
Definition: fall in globules
Antonyms: downpour, life, pour, rise
v
Definition: let go of; fall
Antonyms: ascend, mount, rise, take up
1. Any one of the guttae under the mutules or triglyphs of a Doric entablature.
2. In a cabinet lock, the vertical dimension from the finished edge of the lock to the center of the cylinder or tube.
3. In air conditioning, the vertical distance that a horizontally projected airstream falls from its original elevation when leaving an outlet, measured at the end of the throw.
4. Same as drop curtain.
5. Same as drop panel.
6. Of a stair, a fitting used to close the bottom end of a tubular newel.
7. Same as pendant, 2; also see corner drop.
8. Same as turned drop.
"Drop" is intelligence parlance for the location at which an agent passes information to another, or the act of passing that information—as in "making a drop." In a live drop, the two individuals actually meet. Given the dangers of this, it is more common to employ a "dead drop." The latter term refers to a prearranged spot at which one party passes information to another without actually meeting. Often a dead drop—a term that again refers both to the place and the act—also involves the transfer of money, as when a double agent leaves information for a handler, and the handler returns the favor with cash payment.
It so happens that the most commonly cited examples of drops and dead drops involved agents working for the Soviet bloc during the Cold War. This is probably the case because, for obvious reasons, Western intelligence agencies are not as likely to reveal the methods employed by their own agents.
One oft-cited example is that of John Walker, who passed $1 million of United States Navy secrets to the Soviets before the Federal Bureau of Investigation (FBI) finally caught up with him in 1985. In making his drops, Walker used a garbage bag containing bits of recognizable trash—but nothing that would smell strongly and attract animals—along with documents and other important materials. His KGB handler would in turn leave another bag containing money.
In the same year the FBI caught Walker, the Soviets recruited the FBI's own Robert Hanssen, who accumulated $1.4 million for betraying his country before the authorities caught him in February 2001. At the time of his arrest, Hanssen was making a dead drop under a footbridge at Foxstone Park in Vienna, Virginia.
Further Reading
Books
Nash, Jay Robert. Spies: A Narrative Encyclopedia of Dirty Deeds and Double Dealing from Biblical Times to Today. New York: M. Evans, 1997.
Polmar, Norman, and Thomas B. Allen. Spy Book: The Encyclopedia of Espionage. New York: Random House, 1998.
Electronic
"Traitorous Actions": FBI Agent Charged With Spying for Moscow. <http://abcnews.go.com/sections/us/DailyNews/FBIarrest010220.html> (February 1, 2003).
The difference in price between the front month and back month in a mortgage-backed security (MBS) dollar roll trade. A dollar roll is a popular type of trade in the MBS pass-through TBA market.
According to forward securities pricing theory, the front month price should be higher than the back month price. The drop is a function of current short-term interest rates, prepayment estimates, and the supply and demand for pass-throughs in the current delivery or front month.
Investopedia Says:
A pass-through TBA security is said to be trading through fail when the drop is larger than what it would cost a mortgage originator, investor or securities dealer to fail to deliver into a TBA contract for an entire month. When there is a shortage of supply or extreme demand for a TBA security in the current delivery month, the drop can increase to fail or larger, reflecting the fact that securities dealers would rather roll a trade out an additional month at a large drop or fail to deliver that security for an entire month than make delivery in the current month.
Related Links:
Mortgage-backed securities can offer monthly income, a fixed interest rate and even government backing. Profit From Mortgage Debt With MBS
In the pursuit of Tao, every day something is dropped.
— Lao Tzu, Source: The Tao Te Ching, (48)
LearnThatWord.com is a free vocabulary and spelling program where you only pay for results!
| droopy drawers, droop, drool | |
| drop-in, dropper, dropsy |
1. a minute sphere of liquid as it hangs or falls.
2. a descent or falling below the usual position.

A drop or droplet is a small column of liquid, bounded completely or almost completely by free surfaces. A drop may form when liquid accumulates at the lower end of a tube or other surface boundary, producing a hanging drop called a pendant drop. Drops may also be formed by the condensation of a vapor or by atomization of a larger mass of liquid.
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Liquid forms drops because the liquid exhibits surface tension.
A simple way to form a drop is to allow liquid to flow slowly from the lower end of a vertical tube of small diameter. The surface tension of the liquid causes the liquid to hang from the tube, forming a pendant. When the drop exceeds a certain size it is no longer stable and detaches itself. The falling liquid is also a drop held together by surface tension.
In the pendant drop test, a drop of liquid is suspended from the end of a tube by surface tension. The force due to surface tension is proportional to the length of the boundary between the liquid and the tube, with the proportionality constant usually denoted
.[1] Since the length of this boundary is the circumference of the tube, the force due to surface tension is given by

where d is the tube diameter.
The mass m of the drop hanging from the end of the tube can be found by equating the force due to gravity (
) with the component of the surface tension in the vertical direction (
) giving the formula

where α is the angle of contact with the tube, and g is the acceleration due to gravity.
The limit of this formula, as α goes to 90°, gives the maximum weight of a pendant drop for a liquid with a given surface tension,
.

This relationship is the basis of a convenient method of measuring surface tension, commonly used in the petroleum industry. More sophisticated methods are available when the surface tension is unknown that consider the developing shape of the pendant as the drop grows.[2] [3]
The term droplet is a diminutive form of 'drop' - and as a guide is typically used for liquid particles of less than 500 µm diameter. In spray application, droplets are usually described by their perceived size (i.e., diameter) whereas the dose (or number of infective particles in the case of biopesticides) is a function of their volume. This increases by a cubic function relative to diameter; thus a 50 µm droplet represents a dose in 65 pl and a 500 µm drop represents a dose in 65 nanolitres.
Due to the different refractive index of water and air, refraction and reflection occur on the surfaces of raindrops, leading to rainbow formation.
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The major source of sound when a droplet hits a liquid surface is the resonance of excited bubbles trapped underwater. These oscillating bubbles are responsible for most liquid sounds, such as running water or splashes, as they actually consist of many drop-liquid collisions.[4][5]
The classic shape associated with a drop (with a pointy end in its upper side) comes from the observation of a droplet clinging to a surface. The shape of a drop falling through a gas is actually more or less spherical. Larger drops tend to be flatter on the bottom part due to the pressure of the gas they move through.[6]
Scientists traditionally thought that the variation in the size of raindrops was due to collisions on the way down to the ground. In 2009 French researchers succeeded in showing that the distribution of sizes is due to the drops' interaction with air, which deforms larger drops and causes them to fragment into smaller drops, effectively limiting the largest raindrops to about 6 mm diameter.[7]
A drop of water hitting a wet metal surface and ejecting more droplets, which become water globules and skim across the surface of the water.
A drop of water on a leaf / Hydrophobic effect/ Partial Wetting.
A drop of water on a Asteraceae
| Wikimedia Commons has media related to: Water droplets |
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)
Dansk (Danish)
v. intr. - dryppe, falde, tabes, falde om, ophøre, give op, gå nedad, hælde, hoppe ned, dø
v. tr. - spilde, dryppe, tabe, droppe, sætte af, sende, dæmpe, smide, sænke, føde, afskedige
n. - dråbe, fald, tilbagegang, hængesmykke, pastil, tæppe, faldlem, drink, bestikkelse, brevkasse
idioms:
Nederlands (Dutch)
vallen, laten vallen, intrekken, ophouden, dalen, terloops zeggen, afleveren, weglaten, tegen de vlakte gaan, verspelen, laten varen, val, daling, geheime bergplaats, vrachtje, druppel, oorhanger, helling
Français (French)
v. intr. - tomber, retomber (un objet), tomber goutte à goutte, descendre, se laisser tomber, s'écrouler, s'affaisser, (Théât) tomber (rideau), se calmer, tomber (le vent), baisser (la température, la voix), diminuer (un prix), en rester là, être interrompu, cesser
v. tr. - laisser tomber (un objet), lâcher, laisser tomber, lancer, larguer (une bombe), laisser tomber goutte à goutte, baisser (un prix), déposer (qn, qch), débarquer, (Théât) baisser (rideau), abattre (un oiseau), descendre (qn), laisser échapper (une remarque, un indice), envoyer, écrire à, avaler (un mot, une syllabe), omettre (un mot écrit), supprimer (un mot, une scène), renoncer à, abandonner (un travail), (École) abandonner (une matière), ne pas donner suite à, rompre avec qn, (Sport) écarter (qn), perdre (de l'argent), perdre (cartes, tennis), mettre bas (un animal), prendre (de la drogue)
n. - goutte, larme, (Méd) gouttes, (fig) goutte, pendeloque (chandelier), pendant (boucle d'oreille), pendeloque (collier), pendentif, baisse (température), chute (prix), dénivellation, descente brusque, précipice, hauteur de chute, vide (escalade), trappe, saut (parachute), parachutage, cachette, dépôt clandestin, (US, fig) avantage
idioms:
Deutsch (German)
v. - fallen lassen, senken, fallen, stürzen, sinken, zurückgehen, sich legen, fallenlassen
n. - Tropfen, Gläschen, Sturz, Abnahme, Rückgang, Abwurf
idioms:
Ελληνική (Greek)
v. - στάζω, σταλάζω, πέφτω σε σταγόνες, πέφτω (αναπάντεχα ή απότομα), σωριάζομαι, μου πέφτει κάτω ή από τα χέρια, ρίχνω, βροντάω κάτω, κατεβάζω, χαμηλώνω, παραλείπω, σταματώ, αφήνω στη μέση, κατεβαίνω, εγκαταλείπω ομάδα, ιδέα ή πρόθεση, αποβιβάζω (από όχημα ή σκάφος), κατεβάζω, παρατώ (κάποιον)
n. - σταγόνα, στάλα, ρανίδα, πτώση, πέσιμο, σταγονομετρική δόση φάρμακου, κουφέτο, καραμέλα, παστίλια, γκρεμός, χαράδρα, απόσταση πτώσης, μείωση ποσότητας ή έντασης, αυλαία ή σκηνικό πέτασμα, σημείο απόκρυψης αντικειμένου για παραλαβή από τρίτους
idioms:
Italiano (Italian)
lasciar cadere, calare, ritrattare, cadere, crollare, calmarsi, lasciare perdere, caduta, goccia, bicchierino, ribasso, pendente
idioms:
Português (Portuguese)
v. - pingar, derramar
n. - pingo (m), queda (f)
idioms:
Русский (Russian)
ронять, падать, прекращать, прекращаться, капля, падение, чуть спирта, серьги
idioms:
Español (Spanish)
v. intr. - caer, caerse, desplomarse, calmarse, abandonar, renunciar a, gotear, agacharse, caer herido, moverse suavemente, bajar
v. tr. - dejar caer, bajar, soltar, derogar, revocar, suspender, caer, reducir, disminuir, amainar, abandonar, renunciar a, escribir, descargar, omitir, despedir, pasar por agua
n. - caída, lanzamiento, gota, copa, descenso, baja, pendiente, bajada, pequeña cantidad de algo, una cantidad limitada de bebida alcohólica, depósito, algo que cae o se usa para caer, horca, medallón, pequeña insignia, animal recién nacido
idioms:
Svenska (Swedish)
v. - droppa, falla, sluta, tappa, släppa ned
n. - droppe, örhänge, tår, nedgång
中文(简体)(Chinese (Simplified))
滴下, 掉下, 落下, 下降, 使滴下, 丢失, 放下, 滴, 微量
idioms:
中文(繁體)(Chinese (Traditional))
v. intr. - 滴下, 掉下, 落下, 下降
v. tr. - 使滴下, 丟失, 放下
n. - 滴, 落下, 微量
idioms:
한국어 (Korean)
v. intr. - 떨어지다, 갑자기 주저앉다, 포기하다, 잠깐 들르다
v. tr. - 적하 시키다, 떨어뜨리다, (막 등을) 내리다, ~와 관계를 끊다
n. - 물방울, 소량, 점안제, 하락
idioms:
日本語 (Japanese)
n. - しずく, 一滴, 少量, 少しの酒, 落下物, 落下, 落下距離, 点滴薬, ドロップ, 飴玉
v. - がこぼれる, 滴る, 落ちる, 落下する, 倒れる, 減少する, 低下する, やめる, 打ち切る, 降ろす, 解雇する, 書き送る
idioms:
العربيه (Arabic)
(فعل) يسقط فجأة, يهبط, ينحدر, ينهار من شدة التعب, يرسل رساله لشخص, يقطع صلته بشخص, يبعث بالبريد ( رساله) (الاسم) قطرة, جرعه دوا تعطى على شكل قطرات ( للأذن والأنف خاصه), سقوط
עברית (Hebrew)
v. intr. - נפל, ירד, נטף, חדל
v. tr. - נפל, הפיל, הוריד, הצניח, השמיט, הרפה מ-, נטש, נטף, שלח מכתב, השליך, הפסיק להתרועע עם (מדוברת)
n. - טיפה, נפילה, ירידה, דבר נופל, סוכריה, דבר מוצנח, לגימת משקה, כוס משקה אלכוהולי, תליון או עגיל, גלולה, דלת בגרדום שפתיחתה גורמת לנתלה ליפול, משלוח, מחבוא לסחורה גנו
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