stern vs fundament

stern and fundament both are nouns.

Word	Noun	Adjective	Verb	Adverb
stern	Yes	Yes	No	No
fundament	Yes	No	No	No

As nouns, stern and fundament are synonyms defined as:

stern (noun)	fundament (noun)
the rear part of a ship	lowest support of a structure
the fleshy part of the human body that you sit on	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

stern (adjective)	fundament (adjective)
severe and unremitting in making demands
not to be placated or appeased or moved by entreaty
of a stern or strict bearing or demeanor; forbidding in aspect
severely simple