You know how it smells after it rains? That clean, greenish smell? That’s petrichor, from the Greek petra (stone) and ichor (the blood of Greek gods and goddesses). The term was coined by two Australian researchers in 1964.
Great word to allude to in gardening conversations. Wait till you see the stares as you say "Have you seen my hyponastic grapefruit tree lately?" An odd property of leaves is that the cells on one side often grow faster than the cells on the other, creating the demand for today’s word. The adjective is "hyponastic" and the adverb, "hyponastically." The antonym is epinasty "greater growth on top than on the bottom." This usually causes a downward curve in a leaf.
Etymology: Greek hypo "below, under" + nastos "pressed close" (from nassein "to press"). Greek "hypo" strangely shares an origin with English "up." The original root had a variant with an initial [s] that resulted in Latin sub "under". This root is also related to its antonym, Greek "hyper" (Latin "super"), extended by the common Indo-European suffix -er. Words often share an origin with their antonym, "cold" and "scald," are an example.
A very common slip of the tongue is an antonym substitution, e.g. "I was very cold . . . I mean, hot." Antonyms may be logically antithetical but lexically they form a close relationship.
