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"optimistic" is also used as a crossword clue. If that's what you saw, the answer is often sanguine (8 letters).
Definitions
expecting the best in this best of all possible worlds
Word origin
From optimist + -ic.
Used in a sentence
“in an optimistic mood”
“optimistic plans”
“took an optimistic view”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Expecting good outcomes”10 letters
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