Fickle

прилагательное непостоянный, переменчивый; ненадёжный, неустойчивый, переменный Синоним(ы): inconstant

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Fickle

adjective Etymology: Middle English fikel deceitful, inconstant, from Old English ficol deceitful; akin to Old English befician to deceive, and probably to Old English fāh hostile — more at foe marked by lack of steadfastness, constancy, or stability; given to erratic changeableness Synonyms: see inconstantfickleness nounfickly adverb

Merriam-Webster's Collegiate Dictionary