Inconstant

прилагательное изменчивый, непостоянный, неустойчивый, переменный, переменчивый Синоним(ы): capricious, changeable, fickle, unsteady, unstable, chameleonic Антоним(ы): everlasting, faithful, immutable, invariable, loyal, permanent

Большой англо-русский словарь

Inconstant

adjective Etymology: Middle English, from Middle French, from Latin inconstant-, inconstans, from in- + constant-, constans constant likely to change frequently without apparent or cogent reason • inconstantly adverb Synonyms: inconstant, fickle, capricious, mercurial, unstable mean lacking firmness or steadiness (as in purpose or devotion). inconstant implies an incapacity for steadiness and an inherent tendency to change Example: an inconstant friend. fickle suggests unreliability because of perverse changeability and incapacity for steadfastness Example: performers discover how fickle fans can be. capricious suggests motivation by sudden whim or fancy and stresses unpredictability Example: an utterly capricious critic. mercurial implies a rapid changeability in mood Example: made anxious by her boss's mercurial temperament. unstable implies an incapacity for remaining in a fixed position or steady course and applies especially to a lack of emotional balance Example: too unstable to hold a job.

Merriam-Webster's Collegiate Dictionary