Meaning of CERTAIN in English
Indubitable, unquestionable, indisputable, undeniable, incontestable, incontrovertible, unquestioned, undisputed, undoubted, absolute, positive, plain, sure, past dispute, beyond all question, clear as day.
Sure, assured, confident, undoubting, fully convinced.
Unfailing, infallible, never-failing.
Actual, real, existing.
Settled, determinate, fixed, stated, constant.
Known but unnamed, sort or, some, indeterminate.
Soule. Dictionary of English synonyms. Словарь английских синонимов. 2012