treble vs two-fold

treble is a noun but two-fold is not a noun.

Word	Noun	Adjective	Verb	Adverb
treble	Yes	Yes	Yes	No
two-fold	No	Yes	No	No

As adjectives, treble and two-fold are synonyms defined as:

treble and two-fold: having more than one decidedly dissimilar aspects or qualities

Other synonyms of treble include double, dual, three-fold, threefold, twofold.

treble (noun)	two-fold (noun)
the pitch range of the highest female voice

treble (adjective)	two-fold (adjective)
having or denoting a high range	twice as great or many
three times as great or many	having more than one decidedly dissimilar aspects or qualities
having three units or components or elements
having more than one decidedly dissimilar aspects or qualities

treble (verb)	two-fold (verb)
increase threefold
sing treble