shibboleth
1382, the Heb. word shibboleth "flood, stream," also "ear of corn," in Judges xii:4-6. It was the password used by the Gileadites to distinguish their own men from fleeing Ephraimites, because Ephraimites could not pronounce the -sh- sound. Figurative sense of "watchword" is first recorded 1638, and it evolved by 1862 to "outmoded slogan still adhered to." A similar test-word was cicera "chick pease," used by the Italians to identify the French (who could not pronounce it correctly) during the massacre called the Sicilian Vespers (1282).


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