Definition of shibboleth

• n. - A word which was made the criterion by which to distinguish the Ephraimites from the Gileadites. The Ephraimites, not being able to pronounce sh, called the word sibboleth. See Judges xii.
• n. - Also in an extended sense.
• n. - Hence, the criterion, test, or watchword of a party; a party cry or pet phrase.