pledge vs troth

pledge and troth both are nouns.

Word	Noun	Adjective	Verb	Adverb
pledge	Yes	No	Yes	No
troth	Yes	No	No	No

As nouns, troth is a hyponym of pledge; that is, troth is a word with a more specific, narrower meaning than pledge:

Other hyponyms of pledge include guarantee, warrant, warrantee, warranty, guarantee, plight, vow.

pledge (noun)	troth (noun)
a binding commitment to do or give or refrain from something	a solemn pledge of fidelity
a drink in honor of or to the health of a person or event	a mutual promise to marry
someone accepted for membership but not yet fully admitted to the group
a deposit of personal property as security for a debt

pledge (verb)	troth (verb)
promise solemnly and formally
bind or secure by a pledge
give as a guarantee
propose a toast to
pay (an amount of money) as a contribution to a charity or service, especially at regular intervals