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

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ad. In a distinctive manner; in a way that is notable for its difference.

ad. With distinction; plainly.

In a distinctive manner; with distinction from or opposition (expressed or implied) to something else; peculiarly; characteristically: as, he was by this fact separated distinctively from all the others; this work is distinctively literary.

ad. in an identifiably distinctive manner

"Foreign observers of the islanders, from Hippolyte Taine to Nikos Kazantzakis, have stressed certain distinctively English contributions to civilization, from the country house to the dissemination of Shakespeare to the idea of the "gentleman.""

plainly   

instinctively