In a manner that is beerish; in a way somewhat resembling or characteristic of beer.
Adverb formed from 'beerish' plus -ly, the standard adverbial suffix. This creates an adverb describing the manner or style of an action taken in a beer-like way.
While 'beerily' suggests the effects of drinking beer, 'beerishly' is more about affecting beer-like qualities, though in practice these words overlap so much that 'beerishly' is quite rare in historical usage.
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