In the Book of Judges 12:5-6, we learn that the original shibboleth was an arbitrary word that Jephthah used to spot his enemies: the Ephraimites had trouble with the sh sound, and when asked to pronounce a word with sh in it, they revealed they were enemy spies (“. . . they took him and slew him . . .”).
In its modern sense, a shibboleth is some mannerism, usually linguistic, that reveals your origins – and usually without your being aware of it. Some, like the original shibboleth, are matters of pronunciation. Most Americans, for instance, tend to pronounce the word been as if it were bin, whereas the English tend to say bean. Where the British clearly pronounce both t’s in latter, Americans tend to vocalize the letter t between vowels, pronouncing it as if it were ladder.
Other shibboleths are matters of diction. In formal writing we don’t distinguish singular you from plural you, but many regional dialects do. Y’all is an obvious give-away of someone from the South and youse is common in the New York area; less well known are y’uns or yinz in Pittsburgh and yiz around Philadelphia. The name you use for a long sandwich with various kinds of lunchmeats – hoagie, hero, sub, grinder, poorboy – will similarly reveal where you grew up.
Shibboleths reveal your background, but that doesn’t have to mean location: linguistic habits can also give away your level of education, your profession, your age, your class, and so on. For instance, someone who actually uses whom in conversation is not likely to fit in at a working-class bar. Frequent use of like as a verbal tic says you’re probably youngish. Whether you say pro-life or anti-abortion probably gives away your political position.
The moral of all this? Most traces of regional pronunciation disappear in writing, of course, but plenty of other kinds of shibboleths shine through. A cautious writer will be conscious of the things most people miss, and use them to his or her advantage. The more attention you pay to others’ language and your own, the more sensitive you’ll be and the more you’ll know about how they affect your audience.
– Ken Butera