team vs relay

team and relay both are nouns.

Word	Noun	Adjective	Verb	Adverb
team	Yes	No	Yes	No
relay	Yes	No	Yes	No

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

team (noun)	relay (noun)
a cooperative unit (especially in sports)	the act of passing something along from one person or group to another
two or more draft animals that work together to pull something	electrical device such that current flowing through it in one circuit can switch on and off a current in a second circuit
	a race between teams; each member runs or swims part of the distance
	a crew of workers who relieve another crew
	a fresh team to relieve weary draft animals

team (verb)	relay (verb)
form a team	pass along
	control or operate by relay