block

(computer science) A group of information units (such as records, words, characters, or digits) that are transported or considered as a single unit by virtue of their being stored in successive storage locations; for example, a group of logical records constituting a physical record. The section of a computer memory or storage device that stores such a group of information units. Also known as storage block. To combine two or more information units into a single unit. A contiguous group of text characters that is marked for moving, copying, saving, deletion, or some other word-processing operation.
(design engineering) A metal or wood case enclosing one or more pulleys; has a hook with which it can be attached to an object. cylinder block
(mining engineering) A division of a mine, usually bounded by workings but sometimes by survey lines or other arbitrary limits. In quarrying, a large portion of rock that is removed from the quarry as a solid mass for further processing at a mill.
(petroleum engineering) The subdivision of a sea area for the licensing of oil and gas exploration and production rights.
(statistics) In experimental design, a homogeneous aggregation of items under observation, such as a group of contiguous plots of land or all animals in a litter.

(1) A group of disk or tape records that is stored and transferred as a single unit. On a CD, a block consists of 98 frames of 33 bytes for a total of 3,234 bytes, or 1/75th of a second. See block level.

(2) A group of bits or bytes that is transmitted or processed as a single unit.

(3) A group of text characters that has been marked for moving, copying, saving or other operation.

(4) A rectangular group of pixels that are processed as a unit.

(5) A group of program statements that are treated as a unit based on the results of a comparison.

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A mental obstacle that prohibits a patient from having favorable responses to the dentist and suggested treatment plans.

1. an obstruction or stoppage.
2. regional anesthesia.

• Arthur b. — see segmental dorsolumbar epidural block.
• bundle-branch b. — a form of heart block involving obstruction in one of the branches in the bundle of His.
• field b. — regional anesthesia obtained by blocking conduction in nerves with chemical or physical agents.
• b. grazing — see rotational grazing.
• heart b. — impairment of conduction in heart excitation; often applied specifically to atrioventricular heart block. See also heart block.
• inverted L-b. — linear infiltration cranial and dorsal to the incision site; used for flank laparotomy in cattle and sheep.
• b. mating — mating of all the females in a group during a brief period, e.g. within the span of three estral cycles; a characteristic of seasonal animal farming.
• metabolic b. — the blocking of a biosynthetic pathway due to a genetic enzyme defect or to inhibition of an enzyme by a drug or other substance.
• nerve b. — regional anesthesia secured by injection of an anesthetic in close proximity to the appropriate nerve.
• paracervical b. — anesthesia of the inferior hypogastric plexus and ganglia produced by injection of the local anesthetic into the lateral fornices of the vagina.
• parasacral b. — regional anesthesia produced by injection of a local anesthetic around the sacral nerves as they emerge from the sacral foramina.
• presacral b. — anesthesia produced by injection of the local anesthetic into the sacral nerves on the anterior aspect of the sacrum.
• ring b. — regional anesthesia by the injection of local anesthetic in a complete circle around a limb of a horse, or the teat of a cow.
• sacral b. — anesthesia produced by injection of the local anesthetic into the extradural space of the spinal canal.
• saddle b. — the production of anesthesia in a region corresponding roughly with the areas of the buttocks, perineum and inner aspects of the thighs, by introducing the anesthetic agent low in the dural sac.
• sinus b. — sinus arrest.
• vagal b., vagus nerve b. — blocking of vagal impulses by injection of a solution of local anesthetic into the vagus nerve at its exit from the skull.