white tie vs bow tie

white tie and bow tie both are nouns.

Word	Noun	Adjective	Verb	Adverb
white tie	Yes	No	No	No
bow tie	Yes	No	No	No

As nouns, bow tie is a hypernym of white tie; that is, bow tie is a word with a broader meaning than white tie:

Other hypernyms of white tie include bow-tie, bowtie.

white tie (noun)	bow tie (noun)
bow tie worn as part of a man's formal evening dress	a man's tie that ties in a bow
formalwear consisting of full evening dress for men