promise vs wager

promise and wager both are nouns.

Word	Noun	Adjective	Verb	Adverb
promise	Yes	No	Yes	No
wager	Yes	No	Yes	No

As verbs, wager is a hyponym of promise; that is, wager is a word with a more specific, narrower meaning than promise:

Other hyponyms of promise include read, outguess, second-guess, augur, bet, calculate, forecast, prophesy, vaticinate.

promise (noun)	wager (noun)
grounds for feeling hopeful about the future	the act of gambling
a verbal commitment by one person to another agreeing to do (or not to do) something in the future	the money risked on a gamble

promise (verb)	wager (verb)
make a promise or commitment	maintain with or as if with a bet
promise to undertake or give	stake on the outcome of an issue
make a prediction about; tell in advance
give grounds for expectations