First recorded in 1960–65.
Comes from petro-, a combining form meaning \"rock,\" and ichor, which in classical mythology means “ethereal fluid flowing in the veins of the gods.”
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\r\nEXAMPLES OF PETRICHOR\r\n

The desert landscape was quickly transformed as petrichor filled the air after a long-awaited rainstorm.
As the storm passed, leaving behind puddles and damp earth, the sweet petrichor lingered like a fond memory.

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least upper bound

noun

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