Pocket Thesaurus
Antonyms of certainly
inevitably, certainly, assuredly, plainly, absolutely, indeed, unquestionably, evidently, definitely, undoubtedly, clearly, decidedly, distinctly, indubitably, positively, conclusively, doubtlessly, inexorably, beyond doubt, beyond shadow of doubt, come what may, explicitly, fixedly, for certain, for real, infallibly, irrefutably, manifestly, nothing else but, rain or shine, to be sure, unequivocally, unerringly, unfailingly, unmistakably, unshakably, with certainty, without fail
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