Word of the Week – Trope and Tropical

Did you know that trope and tropical share a root?

This certainly never occurred to me, until I was reading a quote from St. Augustine a few weeks ago that said this:

“Though God is said to change his determinations (so that in a tropical sense the Holy Scripture says even that God repented), this is said with reference to man’s expectations, or the order of natural causes, and not with reference to that which the Almighty had foreknown that he would do.”

Did you scratch your head at that use of tropical? Because I sure did! Clearly, Augustine was not talking about palm trees and the scent of coconut and lovely, sunshine-filled days. I stared at it for a moment, looked at the word, and finally went, “Oh! Like, ‘trope’-ical.”

Those of us in the bookish community are likely familiar with the word trope. A bookish trope is “a common theme or motif.” Like “marriage of convenience” or “love triangle,” for example.

Well, that use of trope follows because the primary definition is “a word or expression used figuratively,” which also came to mean “cliche.” But where did that come from? The original definition was actually “a turn of phrase.”

That’s important–because that’s how it links to tropical as we know the word today. Both share the Greek root trop-, which means “turn.”

So what does a turn have to do with the tropics? The word was used in astronomy to mean “either of the two circles in the celestial sphere which describe the northernmost and southernmost points of the elliptic.” Which is to say, the northern-most or southern-most points after which the sun appears to “turn back” from the equator. These regions on earth happen to be a steady, warm climate, so tropical has of course been applied to things pertaining to those regions, especially having to do with weather and the flora that grows in the regions, and even the colors associated with them.

So Augustine definitely wasn’t talking about palm trees…but he was talking about “a figure of speech which consists in the use of a word or phrase in a sense other than that which is proper to it.”