preliminary vs prelim

preliminary and prelim both are nouns.

Word	Noun	Adjective	Verb	Adverb
preliminary	Yes	Yes	No	No
prelim	Yes	No	No	No

As nouns, preliminary and prelim are synonyms defined as:

preliminary (noun)	prelim (noun)
a minor match preceding the main event	an examination taken by graduate students to determine their fitness to continue
something that serves as a preceding event or introduces what follows	a minor match preceding the main event

preliminary (adjective)	prelim (adjective)
denoting an action or event preceding or in preparation for something more important