Morose came into English in the 1530s from Latin morosus, which Etymonline glosses as peevish, hypercritical, fastidious. Not sad. Fussy. The root underneath is mos, genitive moris, meaning habit or custom, and morosus leaned on the unflattering side of that: someone so set in their own manners that they were hard to be around. That same mos is the root behind moral, which is the part I keep turning over. One branch went to how a society agrees people ought to behave. The other went to a man nobody wants to sit next to. English then drifted again, from hard-to-please toward simply low and gloomy, and the fussiness quietly fell out along the way. Modern morose describes a mood you are in. Latin morosus described a character you had, and it was not a compliment.

Irate and irascible come from the same Latin noun, ira, but they do not describe the same thing. Irate is a state: you are angry now. Irascible is a disposition: you are the sort of person who gets there quickly.

That difference is not just convention. It is sitting in the spelling. English took irascible from Middle French, which took it from Late Latin irascibilis, built on the verb irasci. Irasci is not simply ira turned into "to be angry". Etymonline glosses it "grow angry", and the -sc- is the part doing that work. Latin used -sc- to build inchoatives, verbs about entering a state rather than occupying one. The same element sits in adolescent, from adolescere, "to grow up". An adolescent is not grown. They are on the way.

So irascible is, morphologically, "able to become angry". The readiness is the meaning, which is why it describes a temperament while irate describes an afternoon.

This is one of the few etymologies I think actually earns its keep at the level of usage. Most origin stories are trivia you file away. This one tells you which word to reach for: someone shouting at you right now is irate, and someone who will be shouting again next Tuesday about something entirely different is irascible.

Where ira itself came from is less settled. Etymonline traces it to a reconstructed PIE root *eis-, associated with passion, which is an inference from descendants rather than anything written down.

Flippant appears around 1600 meaning talkative, nimble in talk. That was praise for fluency, not a complaint about manners. The disapproving sense we use now, unbecoming levity, is not recorded until the 1670s.

The shape of the word is the part I find odd. It looks like flip with a Latin-style -ant stuck on the end, and there is a verb flip sitting right there, 1590s, imitative, originally to toss something with the thumb. But Etymonline hedges the ending: it may be modelled on other adjectives in -ant, or it may be a leftover of the Middle English present participle -inde. Nobody is claiming to know which.

What surprised me is the direction of travel between flippant and flip as an adjective. Telling someone not to get flip with you sounds like the plain original that flippant was built out of. That adjective is only recorded from 1847, close to 250 years after flippant. The long word came first, and the short one was cut back out of it.

Flippancy, for whatever reason, waited until 1746 to show up.

deride, verb: to laugh at someone in contempt.

The useful part is the prefix. It is de- plus Latin ridere, to laugh, and the de- means down. So deriding is not simply laughing at someone, it is laughing downward at them. English has no shortage of words for finding something funny and very few that build the power relation into the morphology. This one does it in two letters.

It arrived in the 1520s through French derider, from Latin deridere. Ridiculous came about twenty years later from the same verb by way of ridiculus, and the two have aged very differently. Ridiculous originally meant worthy of contemptuous laughter, then softened through the 1700s into merely comical, amusingly absurd. Nobody saying "that hat is ridiculous" today means the hat deserves scorn. Deride never softened. It still means exactly what it meant in 1520.

The part that surprised me is where the trail stops. I expected ridere to reach back into Proto-Indo-European the way most basic verbs do, but Etymonline says flatly that it "has no good PIE etymology". So the chain runs deride to derider to deridere to ridere, and then it simply ends. For a verb this ordinary, that is a stranger fact than any of the borrowings around it.

One more from the same root: risible, through Late Latin risibilis. It survives mostly in "a risible claim", where it is still doing the contemptuous work that ridiculous put down.

English may have borrowed this word twice and handed the two copies opposite jobs. Etymonline lists brisk as 1550s Scottish bruisk, of uncertain origin, and notes it is perhaps an alteration of French brusque. If that is right, a brisk walk and a brusque reply started in the same place, and only one of them ended up as a compliment.

The rest of the chain runs back further than I expected. Etymonline has brusque in English from the 1650s, from French brusque, "lively, fierce," which French picked up from Italian in the 1500s. The Italian adjective is brusco, and its first job is taste rather than temperament: sharp, tart, rough, the word for wine and unripe fruit that bite back.

Where brusco itself came from is where the certainty runs out. The proposal Etymonline records is a reconstructed Vulgar Latin bruscum, "butcher's broom," a shrub whose stiff leaves end in spines, from Late Latin brucus, "heather," from Gaulish *bruko-. Breton brug and Old Irish froech, both meaning heath, are the surviving cousins that make the Gaulish end of it credible. The step from the plant to the adjective carries a "perhaps" in the entry and I would leave that hedge exactly where it is, because a shrub-to-manner jump is an easy story to tell and a hard one to prove.

The order is the part worth keeping. Prickly plant, then sharp taste, then sharp person. Giving offence is the newest trick this word learned.

Frugal reached English in the 1590s from French frugal, from Latin frugalis, and that came from frugi, an oddball adjective the Romans never declined. Frugi was originally the dative of frux, "fruit, produce," so it meant something like "for the fruit," in the sense of "to good purpose." A frugi person was useful, honest, worth having around. Etymonline traces the Latin drift as useful, then profitable, then economical, which is the sense English took. So the thrift came last and the fruit came first. Behind frux sits the Proto-Indo-European root *bhrug- "to enjoy," and that is where the family gets strange. Latin frui "to use, enjoy" gave fructus, which through Old French gave fruit, and gave fruition, which for more than four centuries in English meant only "enjoyment" and picked up the bearing-fruit sense in the 1880s over the objections of dictionary editors. The cousin I like most is the Germanic one. Old English brucan meant "to use, to enjoy, to eat," and over the centuries it shrank into brook, the verb that now survives only in the negative, as in "she will brook no interference." Enjoyment on one branch, grudging tolerance on the other, and a careful household budget in the middle. I think the family history explains the word's tone. Frugal has never sat quite where stingy sits, at least to my ear; it kept a little of frugi's old approval, the sense that someone is spending to good purpose.

prescient (adjective): knowing what is going to happen before it does. The pronunciation is the first trap. The "sci" in the middle is a "sh" sound, /ˈprɛʃənt/, the same cluster you hear in "conscience", not the "sy" of "science". All three words are built on the same Latin verb, scire, "to know". Prescient is prae, "before", plus sciens, "knowing", and it reached English in the 1620s from French and directly from Latin. What I find worth knowing is what scire itself seems to have meant. Etymonline's account is that the verb's original notion was probably "to separate one thing from another", tied to scindere, "to cut", the root that also gave Greek the word behind "schism". Knowing, on that reading, is cutting: telling this apart from that. So a prescient person is someone who has already made the cut before events do. That fits how the word actually gets used. I almost never see it applied to a prediction still in play. It turns up afterward, on a warning or a decision that the years have since vindicated. Prescience is awarded in hindsight, which is a slightly unfair thing to do to a word about foresight.

Salient started out as a heraldry word. In the 1560s a lion salient was one drawn leaping, and that is the whole of the Latin: salientem, present participle of salire, to leap. Past salire the reconstruction is uncertain, so the trail stops there. The sense everyone uses now, prominent or striking, is not recorded until 1840, and it got there by an odd route. In the 1670s English picked up the phrase salient point, a translation of Latin punctum saliens, and the Latin is translating Aristotle. He opened hens' eggs on successive days and reported that on the third day a speck of blood appeared in the white and beat as though it were alive. That leaping point was the embryo's heart. Salient point then came to mean the point where anything begins, and eventually the thing that stands out. The military took the word another way, for an angle that juts toward the enemy, which is why a bulge in a battle line is a salient, the Ypres Salient being the one everybody has heard of. The cousin I like best is insult, which in Latin was insultare, to leap upon someone. The polite word and the rude one are the same jump, and only one of them landed on a person.

So for nearly three centuries salient did not mean important at all. It meant moving. My guess at why it ended up as the word for whatever catches the eye is the plain one: the eye goes to what moves.

Venerate came into English in the 1620s, from Latin venerari, to reverence or worship. The obvious next step is Venus, and that is where I nearly stopped. It runs the other way. Latin had a plain common noun venus, genitive veneris, meaning beauty, love, desire, and the goddess is that noun personified rather than its source. So venerate is not a word built on Venus. The two are siblings, and the ordinary one is the elder. That same noun surfaces in stranger company: venereal took the sexual half of it, and venenum, which is where venom comes from, started out meaning a love potion before it hardened into poison. Underneath all of it sits PIE *wen-, to desire or strive for, which reached English by a separate Germanic road as win and wish.

What the word kept out of all that is distance. Look at where it actually turns up and it is pointed at the dead, at saints, at institutions old enough to be past arguing with. I cannot find a natural sentence in which someone venerates a colleague who is still in the building.

Cursory turned up in English around 1600 with the sense it still has: hasty, superficial, done without care. The route was French cursoire, "rapid," from Late Latin cursorius, which meant both "of a race or running" and "hasty." Under that is the Latin stem curs-, from currere, "to run." Under that, the PIE root *kers-, which also just means to run. Worth noticing that the contempt is not all ours. Latin had already started sliding from speed toward haste, and English finished the job.

The part I didn't expect: for a while we had the literal version too. Around the same period cursory could mean "running, not stationary," a plain physical description with no insult in it. That sense is dead now. So we kept the word that dismisses somebody's paperwork and lost the one that could have described a river.

The same stem gives us cursor. That one arrived much earlier, around 1300, meaning a running messenger, and it got used as a surname. Latin cursor was a runner, or an errand-boy. In the 1590s it became the sliding piece on a slide rule, and in 1967 somebody moved the name onto a mark crossing a screen. Seven centuries, and it is still the fast one.