The word trajectory is a noun. The plural form is trajectories.
noun
Circumference is a noun.
"Ellipse" is a noun.
Quadrilateral can be used as a noun and an adjective.
"Curved" refers to something that deviates from a straight line. It may refer to a bend in the road, a line on a graph, or the trajectory of a baseball.
A projectile has minimum speed at the top of the trajectory.
part of speech
The part of speech for this particular word is a noun.
A sentence for trajectory: The detectives were determining the trajectory of the bullet.
what part of speech is beneath
adverb
what part of speech is work
Sashay is a verb. It means to walk in an exaggerated, showy manner, often with hip swaying.
"Did not" or "didn't" is a contraction of the auxiliary verb "did" and the adverb "not," forming a negative past tense construction in English.
The word speech is a noun.
Adjective
Yes, a proper noun is a type of noun that specifically names a unique person, place, thing, or idea and is typically capitalized. It is part of the broader category of nouns in the classification of parts of speech in grammar.