kicker vs placekicker

kicker and placekicker both are nouns.

Word	Noun	Adjective	Verb	Adverb
kicker	Yes	No	No	No
placekicker	Yes	No	No	No

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

Other hyponyms of kicker include dropkicker, place-kicker, punter.

kicker (noun)	placekicker (noun)
a player who kicks the football	(football) a kicker who makes a place kick for a goal