adjective Date: 14th century indefinite , indeterminate , not certain to occur ; problematical , not reliable ; untrustworthy , 4. not known beyond doubt ; dubious , not having certain knowledge ; doubtful , not clearly identified or defined , not constant ; variable , fitful , ~ly adverb ~ness noun
UNCERTAIN
Meaning of UNCERTAIN in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012