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advertent / æd-vêrt-ênt / adjective

Attentive, heedful, aware.

This rarely used word, Dr. Goodword writes,  is the adjective of the verb advert "take heed of, pay attention to" (as opposed to avert "turn away from"). Its negative correlate, inadvertent "inattentive, heedless" is used so much more frequently, it is often taken as an orphan negative, a negative without a corresponding positive. The verb is also related to advertisement, a noun which the British reduce to advert, too. Americans trim it all the way back to ad.

If you studied Latin, as I did, you'll know something of the history of this word.

Advertent  comes to us from Latin advertere "turn toward," from ad "toward" + vertere "to turn"—hmm...adds up, doesn't it? Both the English words versus and adverse are related to this Latin stem. The root that morphed into this Latin verb came into the Germanic languages as *werth, which ended up as English -ward "in the direction of", heard in words like toward, westward, and homeward. We should also be advertent of the fact that the E and R traded places at some point in a process known as metathesis, so that the same root gave us writhe and wreath, both involved somehow with turning.