A shibboleth is a kind of linguistic password: A way of speaking (a pronunciation, or the use of a particular expression) that identifies one as a member, or a non-member, of a particular group. The group has some kind of social power to set the standards for who belongs to the group: who is "in" and who is "out".
The purpose of a shibboleth is exclusionary as much as inclusionary: A person whose way of speaking violates a shibboleth is identified as an outsider and thereby excluded by the group. (This phenomenon is part of the "Judge a book by its cover" tendency apparently embedded in human cognition, and the use of language to distinguish social groups. The idea here is that some superficial characteristic is taken as a signal for how to view the person who has it--usually, "good" if the person is in the group, "bad" if the person is judged to be outside the group.)
The story behind the word is recorded in the biblical Book of Judges. The word shibboleth in ancient Hebrew dialects meant 'ear of grain' (or, some say, 'stream'). Some groups pronounced it with a sh sound, but speakers of related dialects pronounced it with an s.
In the story, two Semitic tribes, the Ephraimites and the Gileadites, have a great battle. The Gileadites defeat the Ephraimites, and set up a blockade to catch the fleeing Ephraimites. The sentries asked each person to say the word shibboleth. The Ephraimites, who had no sh sound in their language, pronounced the word with an s and were thereby unmasked as the enemy and slaughtered.
Here is the relevant excerpt from the Book of Judges. The full account is in Chapter 12, verses 1-15.
12, 4 Then Jephthah gathered together all the men of Gilead, and fought with Ephraim: and the men of Gilead smote Ephraim, because they said, Ye Gileadites are fugitives of Ephraim among the Ephraimites, and among the Manassites.
5 And the Gileadites took the passages of Jordan before the Ephraimites: and it was so, that when those Ephraimites which were escaped said, Let me go over; that the men of Gilead said unto him, art thou an Ephraimite? If he say Nay;
6 Then said they unto him, Say now Shibboleth: and he said Sibboleth: for he could not frame to pronounce it right. Then they took him, and slew him at the passages of Jordan: and there fell at that time of the Ephraimites forty and two thousand.
© 2008 Suzanne Kemmer
Last modified 24 Sept 08