bunker vs foxhole

bunker and foxhole both are nouns.

Word	Noun	Adjective	Verb	Adverb
bunker	Yes	No	Yes	No
foxhole	Yes	No	No	No

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

bunker: a fortification of earth; mostly or entirely below ground
foxhole: a small dugout with a pit for individual shelter against enemy fire

Other hyponyms of bunker include fox hole, funk hole.

bunker (noun)	foxhole (noun)
a hazard on a golf course	a small dugout with a pit for individual shelter against enemy fire
a fortification of earth; mostly or entirely below ground
a large container for storing fuel

bunker (verb)	foxhole (verb)
hit a golf ball into a bunker
transfer cargo from a ship to a warehouse
fill (a ship's bunker) with coal or oil