Since we know this word mainly from its slot in the phrase kith and kin, it has the feel of an orphan and a fossil: an old word that would disappear entirely if not for its supported use in a phrase. But in fact kith, which means "familiar people" (friends, neighbors, and the like) is related to couth, a word known mainly from its slot in uncouth. Both words have ancestors in Old English.

In the spirit of having a word for everything, today's noun is the name for the greenish-blue deposit that develops on some metals (such as copper and bronze) when they're exposed to the elements for some time. Verdigris is also a pigment used in paints that is made from this substance. The word was borrowed from French in the 14th century, and literally means "green of Greece."

No one likes things that rankle (that is, make you resentful or angry), but you might be content with rankling if its etymon were the alternative. Rankle derives ultimately, via various twists and turns, from dracunculus, the Latin diminutive of draco, which means, and gives us, "dragon." An intermediate meaning of this word route was "festering sore," which suggests a little more clearly how rankle came to its modern meaning.

Words that aim to inflame, provoke, or aggravate come in many flavors in English. When you wish to oppose someone directly, openly, and unambiguously, polemic may be the right genre for you: it comes from polemos, the Greek word for war. Modern usage of the word is often with a negative connotation, to characterize the belligerent statements of someone other than yourself.

There are chords, and then there are cords. How do you keep them all separate? With great difficulty, because the two words have a somewhat incestuous history, and the spelling chord, to boot, represents two different words. Three or more notes sounded together is a chord; that's one word. A line connecting two points on a circle is a chord; that's another word. Vocal cords and spinal cords are different things, though anatomical structures sometimes use the spelling chord, and you can use your vocal cords to produce chords. Just so you know.