In a manner that opposes optimism; with skepticism, pessimism, or a negative outlook about future outcomes.
From anti- + optimistically (in an optimistic manner). The term follows standard English adverb formation but is not commonly used, with 'pessimistically' being the preferred alternative.
While 'pessimistically' is the standard word, 'antioptimistically' is technically correct but so rare that using it might make people do a double-take—language sometimes creates new words even when perfectly good ones already exist.
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