Somewhat dank; slightly damp, wet, or having a somewhat unpleasant moisture quality.
From 'dank' plus the suffix '-ish' (indicating a somewhat lesser degree of a quality, from Old English origin).
The suffix '-ish' is brilliant for English — it lets you express 'kind of damp' or 'somewhat wet' in a single word, which is why you hear 'dankish' more often than 'somewhat dank.'
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