grinder vs meat grinder

grinder and meat grinder both are nouns.

Word	Noun	Adjective	Verb	Adverb
grinder	Yes	No	No	No
meat grinder	Yes	No	No	No

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

grinder (noun)	meat grinder (noun)
a machine tool that polishes metal	any action resulting in injury or destruction
machinery that processes materials by grinding or crushing	a mill for grinding meat
grinding tooth with a broad crown; located behind the premolars
a large sandwich made of a long crusty roll split lengthwise and filled with meats and cheese (and tomato and onion and lettuce and condiments); different names are used in different sections of the United States