Spectacular

google

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late 17th century: from spectacle, on the pattern of words such as oracular .

wiktionary

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From Latin spectaculum(“a sight, show”) + -ar

etymonline

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spectacular (adj.)

1680s, from Latin spectaculum "a sight, show" (see spectacle) + -ar. As a noun, attested by 1890. Related: Spectacularly.