triad vs trey

triad and trey both are nouns.

Word	Noun	Adjective	Verb	Adverb
triad	Yes	No	No	No
trey	Yes	No	No	No

As nouns, triad and trey are synonyms defined as:

triad and trey: the cardinal number that is the sum of one and one and one

triad (noun)	trey (noun)
a three-note major or minor chord; a note and its third and fifth tones	one of four playing cards in a deck having three pips
three people considered as a unit	the cardinal number that is the sum of one and one and one
a set of three similar things considered as a unit
the cardinal number that is the sum of one and one and one