This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

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ad. Without question and beyond doubt.

ad. In a definite manner; decisively.

ad. In a definite manner; with precision; precisely; determinately.

In a definite manner.

ad. without question and beyond doubt

"Borderline cases, symptomatic of vagueness, are cases to which the predicate neither definitely applies nor definitely doesn't apply, where ˜definitely™ is now given a semantic analysis as opposed to an epistemic one."

precisely    determinately   

indefinitely