mover vs coaster

mover and coaster both are nouns.

Word	Noun	Adjective	Verb	Adverb
mover	Yes	No	No	No
coaster	Yes	No	No	No

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

mover (noun)	coaster (noun)
a company that moves the possessions of a family or business from one site to another	a covering (plate or mat) that protects the surface of a table (i.e., from the condensation on a cold glass or bottle)
someone who moves	someone who coasts
(parliamentary procedure) someone who makes a formal motion	a resident of a coastal area
workman employed by a moving company