amphibrach vs metrical foot

amphibrach and metrical foot both are nouns.

Word	Noun	Adjective	Verb	Adverb
amphibrach	Yes	No	No	No
metrical foot	Yes	No	No	No

As nouns, metrical foot is a hypernym of amphibrach; that is, metrical foot is a word with a broader meaning than amphibrach:

amphibrach: a metrical unit with unstressed-stressed-unstressed syllables (e.g., `remember')
metrical foot: (prosody) a group of 2 or 3 syllables forming the basic unit of poetic rhythm

Other hypernyms of amphibrach include foot, metrical unit.

amphibrach (noun)	metrical foot (noun)
a metrical unit with unstressed-stressed-unstressed syllables (e.g., `remember')	(prosody) a group of 2 or 3 syllables forming the basic unit of poetic rhythm