raft foundation vs fundament

raft foundation and fundament both are nouns.

Word	Noun	Adjective	Verb	Adverb
raft foundation	Yes	No	No	No
fundament	Yes	No	No	No

As nouns, fundament is a hypernym of raft foundation; that is, fundament is a word with a broader meaning than raft foundation:

raft foundation: a foundation (usually on soft ground) consisting of an extended layer of reinforced concrete
fundament: lowest support of a structure

Other hypernyms of raft foundation include base, foot, foundation, groundwork, substructure, understructure.

raft foundation (noun)	fundament (noun)
a foundation (usually on soft ground) consisting of an extended layer of reinforced concrete	lowest support of a structure
	the fleshy part of the human body that you sit on
	the fundamental assumptions from which something is begun or developed or calculated or explained