In what follows, “accent mark” will be used in a loose sense to include all diacritical marks that guide pronunciation. Operating systems and programs differ in how they produce accent marks, but it’s worth learning how yours works. Writing them in by hand afterwards looks amateurish.
Words adopted from foreign languages sometimes carry their accent marks with them, as in “fiancé, ” “protégé,” and “cliché.” As words become more at home in English, they tend to shed the marks: “Café” is often spelled “cafe.” Unfortunately, “résumé” seems to be losing its marks one at a time (see under “vita/vitae”).
Many computer users have not learned their systems well enough to understand how to produce the desired accent and often insert an apostrophe (curled) or foot mark (straight) after the accented letter instead: “cafe’.” This is both ugly and incorrect. The same error is commonly seen on storefront signs.
So far we’ve used examples containing acute (right-leaning) accent marks. French and Italian (but not Spanish) words often contain grave (left-leaning) accents; in Italian it’s a caffè. It is important not to substitute one kind of accent for the other.
The diaeresis over a letter signifies that it is to be pronounced as a separate syllable: “noël” and “naïve” are sometimes spelled with a diaeresis, for instance. The umlaut, which looks identical, modifies the sound of a vowel, as in German Fräulein (girl), where the accent mark changes the “frow” sound of Frau (woman) to “froy.” Rock groups like “Blue Öyster Cult” scattered umlauts about nonsensically to create an exotic look.
Spanish words not completely assimilated into English like piñata and niño retain the tilde, which tells you that an “N” is to be pronounced with a “Y” sound after it.
In English-language publications accent marks are often discarded, but the acute and grave accents are the ones most often retained.
In referring to singing unaccompanied by instruments, the traditional spelling is the Italian one, a cappella: two words, two Ps, two Ls. The Latin spelling a capella is learned, but in the realm of musical terminology, we usually stick with Italian. The one-word spelling “acapella” is widely used by Americans, including by some performing groups, but this is generally regarded by musical experts as an error.
Although some academics are undoubtedly nuts, the usual English-language pronunciation of “academia” does not rhyme with “macadamia.” The third syllable is pronounced “deem.” Just say “academe” and add “ee-yuh.” However, there’s an interesting possibility if you go with “ack-uh-DAME-ee-yuh: although some people will sneer at your lack of sophistication, others will assume you’re using the Latin pronunciation and being learned.
Most people first encounter “obtuse” in geometry class, where it labels an angle of more than 90 degrees and less than 180. Imagine what sort of blunt arrowhead that kind of angle would make and you will understand why it also has a figurative meaning of “dull, stupid.” But people often mix the word up with “abstruse,” which means “difficult to understand.”
When you mean to criticize something for being needlessly complex or baffling, the word you need is not “obtuse,” but “abstruse.”
Although it’s “absorbed” and “absorbing,” the correct spelling of the noun is “absorption.”
But note that scientists distinguish between “absorption” as the process of swallowing up or sucking in something and “adsorption” as the process by which something adheres to the surface of something else without being assimilated into it. Even technical writers often confuse these two.
“AM” stands for the Latin phrase Ante Meridiem —which means “before noon”—and “PM” stands for Post Meridiem : “after noon.” Although digital clocks routinely label noon “12:00 PM” you should avoid this expression not only because it is incorrect, but because many people will imagine you are talking about midnight instead. The same goes for “12:00 AM.” You can say or write “twelve noon,” “noon sharp,” or “exactly at noon” when you want to designate a precise time.
It is now rare to see periods placed after these abbreviations as in “A.M.”; but in formal writing it is still preferable to capitalize them, though the lower-case “am” and “pm” are now so popular they are not likely to get you into trouble.
Occasionally computer programs encourage you to write “AM” and “PM” without a space before them, but others will misread your data if you omit the space. The nonstandard habit of omitting the space is spreading rapidly, and should be avoided in formal writing.
If you offer pie à la mode on your menu, be careful not to spell it “ala mode” or—worse—“alamode.” The accent over the first “a” is optional in English, although this is an adaptation of the French phrase à la mode de meaning “in the manner of.” The one-word spelling used to be common, but as people became more sensitive to preserving the spelling of originally French phrases, it fell out of favor. In whose manner is it to plop ice cream on your pie? Nobody really knows, but it’s yummy. Stick with the two-word spelling in all other uses of the phrase “à la” as well.