64 synonyms for promise such as be a sign of, agreement, ability, assure, augur, and be a presage of. Promise is a noun, and its antonyms are breach and break.
Agreement, assurance, bond, commitment, compact, contract, covenant, guarantee, oath, pledge, undertaking, vow, word, and word of honour.
Ability, aptitude, capability, capacity, flair, potential, potentiality, and talent.
Assure, bind oneself, commit oneself, contract, covenant, engage, give an assurance, give an undertaking, give one's word, guarantee, pledge, plight, swear, swear/take an oath, undertake, and vow.
Augur, be a presage of, be a sign of, be evidence of, bespeak, betoken, bode, denote, forebode, foreshadow, foretoken, give an/every indication of, give hope of, harbinger, herald, hint at, hold out hopes of, indicate, lead one to expect, point to, portend, presage, show signs of, signify, and suggest.