contest vs contention

contest and contention both are nouns.

Word	Noun	Adjective	Verb	Adverb
contest	Yes	No	Yes	No
contention	Yes	No	No	No

As nouns, contention is a hypernym of contest; that is, contention is a word with a broader meaning than contest:

Other hypernyms of contest include competition, rivalry.

contest (noun)	contention (noun)
a struggle between rivals	the act of competing as for profit or a prize
an occasion on which a winner is selected from among two or more contestants	a contentious speech act; a dispute where there is strong disagreement
	a point asserted as part of an argument

contest (verb)	contention (verb)
to make the subject of dispute, contention, or litigation