Today we’ll home in on three examples of the English language’s capriciousness.

Self-deprecating  Few contemporary writers would hesitate to use self-deprecating to describe someone who is refreshingly humble. But the term’s wide acceptance is yet another triumph of the slobs over the snobs.

Technically, the correct term is self-depreciating. Although deprecate and depreciate appear almost identical, these words have different roots, and different meanings as well. Traditionally, to deprecate is to disapprove of or denounce. To depreciate is to devalue or downgrade. Because the two words are easily confused, most dictionaries caved forty or fifty years ago and started listing them as synonymous.

Why did self-deprecating prevail when self-depreciating is the right choice? Possibly because deprecating sounds mysterious and swanky.

It’s not as much fun to use depreciating, with its unwieldy extra syllable. It’s a dreary word that evokes decline and obsolescence.

Momentarily  Since the mid-seventeenth century, momentarily has meant “for a moment.” But in the twentieth century, casual speakers and writers started using it to mean “in a moment.” This johnny-come-lately meaning of momentarily has caught up with and maybe overtaken the traditional meaning.

There is quite a difference between for a moment and in a moment when you think about it. Most travelers are heartened when they hear “Passengers’ baggage will arrive momentarily.” But this announcement could be stressful news to traveling language sticklers—they might take it to mean that their arriving luggage will disappear after only a few seconds.

So why say something like Let’s speak momentarily and risk being misinterpreted? The solution is to drop momentarily and instead say either Let’s speak soon or Let’s have a short talk.

Presently  This word has changed meanings more than once since its arrival in the fourteenth century. At first it meant now. But today careful speakers and writers use it to mean “in the near future.” Others use it in its original sense. The 2014 edition of Webster’s New World lists both “in a little while; soon” and “at present; now: a usage still objected to by some.”

We recommend that you avoid this fussy word. If you tell a houseful of ravenous guests, “We are serving dinner presently,” many will think you mean right now and start elbowing their way to the front of the line.

Good alternative: “We are serving dinner soon.”
Not so good alternative: “We are serving dinner momentarily.”