KJV Dictionary Definition: shibboleth
SHIB'BOLETH, n. Heb. an ear of corn, or a stream of water.
1. A word which was made the criterion by which to distinguish the Ephraimites not being able to pronounce the letter sh, pronounced the word sibboleth. See Judges 12. Hence,
2. The criterion of a party; or that which distinguishes one party from another; and usually some peculiarity in things of little importance.