proportional font vs typeface

proportional font and typeface both are nouns.

Word	Noun	Adjective	Verb	Adverb
proportional font	Yes	No	No	No
typeface	Yes	No	No	No

As nouns, typeface is a hypernym of proportional font; that is, typeface is a word with a broader meaning than proportional font:

proportional font: any font whose different characters have different widths
typeface: a specific size and style of type within a type family

Other hypernyms of proportional font include case, face, font, fount.

proportional font (noun)	typeface (noun)
any font whose different characters have different widths	a specific size and style of type within a type family