Lager lout of the air.

Dear Word Detective: My wife came across a word we don’t know in a novel she is reading. Here is how it was used: “Gladly, just as soon as a certain arrogant jackdaw is gone from my home.” The word is “jackdaw.” — Rick.

And a fine word it is, too. You don’t even have to know what “jackdaw” means to know it’s an insult. You can somehow tell that it’s never going to crop up in a sentence like “The new hire at work is a brilliant young jackdaw with a bright future” (unless you’re listening to a master of sarcasm). You’re more likely to find “jackdaw” in a complaint of slander, as in “Plaintiff alleges that defendant, in the presence of his children, called him a ‘scoundrel,’ a ‘guttersnipe’ and a ‘jackdaw.'”

None of this is really fair to the actual “jackdaw,” which is an innocent little bird with above-average intelligence. The jackdaw (Corvus monedula) is a member of the crow family, perhaps a bit smaller than standard crows, but known for its ability to imitate human speech and its eagerness to do so. The original name of the jackdaw was simply “daw,” from the Middle English “dawe,” based on a Germanic root that itself was probably simply an imitation of the bird’s call. “Jack” (a familiar form of the name John) is often tacked onto animal names to denote either “male” (as in “jackass”) or “small sized” (as in “jackdaw”).

According to the Oxford English Dictionary, the jackdaw is “noted for its loquacity and thievish propensities,” which apparently means that when the bird isn’t actively looting your house it’s driving you nuts with its babbling. This brings us to the use of “jackdaw,” beginning in the early 17th century, as a derogatory term for a loud, talkative and obnoxious person, the sense your wife encountered in her novel. “Jackdaw” is fairly rarely heard today, but we really ought to revive the term. The species, after all, is far from extinct.

Interestingly, jackdaws (the feathered kind) were suffering from a bad reputation even before their name became an insult. Aesop featured jackdaws in no fewer than six of his fables, none showing the bird in a good light. In the most famous, “The Jackdaw and the Peacocks,” a jackdaw comes across some feathers shed by the brilliantly colored birds and decides to impersonate a peacock by donning the plumage. The peacocks, however, are not fooled and reject him. So he returns home to his jackdaw flock, but they, too, now reject him, saying, “If you had been content to dwell among us, satisfied with what Nature had bestowed on you, then you would not have been humiliated by the peacocks, nor would your disgrace have met with our rebuff.” One wonders what Aesop would have to say about plastic surgery.

The cranky reindeer.

Dear Word Detective: I know when something “gets my dander up,” which is something my mother always used to say, but what does it mean? Also, is it any relation to the cat dander that results from my household of four cats? As an aside, I’ve been told (and firmly believe) that six is the official threshold between generous cat lover and weird sociopathic cat person, so I consider myself safe and healthy. Et tu? — Carl, at work in da Bronx.

Hmm. Is that six cats per person, or a household total of six? There are some cats around here that definitely aren’t mine, such as Phoebe, who slashes at me whenever I walk past her Special Chair. Or Little Girl Cat, who apparently resents the fact that we ran out of names. Saving her from certain death-by-coyote evidently wasn’t sufficient. She wanted to be named Tiffani or Ashleigh or or something.

Due to our, uh, several cats, our house is not normally in a state where we would notice any cat dander. But I think it’s interesting that “dander” in the “stuff that falls from pets and makes you sneeze” sense is the same flaky detritus that is known, in the case of humans, as “dandruff.” “Dandruff” and this sort of “dander” are both just flakes of dead skin from the scalp, which in humans covers just the top of the head but in animals is more of a full-body affair. The origin of “dandruff,” which first popped up in English around 1545, is unknown, but the “ruff” part may be related to the old English dialect word “huff,” meaning “scab.”

The use of “dander” in “get one’s dander up,” meaning “to anger, to provoke someone’s temper,” may or may not be related to the “dead skin” kind of “dander.” If it is, the sense may be similar to “get one’s back up,” also meaning to anger, drawn from the action of a cat arching its back when threatened. Perhaps when one gets very angry one sheds more dandruff. Beats me.

It would make a bit more sense if, as one theory has it, “get one’s dander” referred to another kind of “dander,” perhaps a mutated form of the Dutch “donder,” meaning “thunder.” The equation of “anger” with “thunder” makes perfect sense. Unfortunately, there is no direct evidence for such a derivation. (By the way, Santa’s seventh reindeer was originally named “Donder,” not “Donner.” “Donder,” thunder, was of a pair with “Blitzen,” meaning lightning.)

Another theory ties “dander” in the “anger” sense to “dunder,” a West Indian word for the fermented cane juice used in the manufacture of rum. But I still find the “donder” theory more convincing.

Whatever the origin, “to get one’s dander up” is considered an American invention, first appearing in the early 19th century, and still very much in use today.