contact vs collision

contact and collision both are nouns.

Word	Noun	Adjective	Verb	Adverb
contact	Yes	No	Yes	No
collision	Yes	No	No	No

As nouns, collision is a hyponym of contact; that is, collision is a word with a more specific, narrower meaning than contact:

contact: the physical coming together of two or more things
collision: (physics) a brief event in which two or more bodies come together

Other hyponyms of contact include hit, engagement, interlocking, mesh, meshing, flick, impact, touch, touching.

contact (noun)	collision (noun)
the act of touching physically	a conflict of opposed ideas or attitudes or goals
close interaction	an accident resulting from violent impact of a moving object
(electronics) a junction where things (as two electrical conductors) touch or are in physical contact	(physics) a brief event in which two or more bodies come together
a thin curved glass or plastic lens designed to fit over the cornea in order to correct vision or to deliver medication
a channel for communication between groups
a communicative interaction
the physical coming together of two or more things
a person who is in a position to give you special assistance
the state or condition of touching or of being in immediate proximity

contact (verb)	collision (verb)
be in or establish communication with
be in direct physical contact with; make contact