Shibboleth

A shibboleth (/ˈʃɪbəˌlɛθ, -əlᵻθ/) ( listen ) is a word or custom whose variations in pronunciation or style are used to differentiate members of ingroups from those of outgroups, with each receiving value judgments of superior or inferior.

Over time, the word has also evolved to signify an old belief or saying that is repetitively cited but untrue. As an illustration of this usage the Concise Oxford Dictionary cites "[We] must abandon outdated shibboleths".

The term originates from the Hebrew word shibbólet (שִׁבֹּלֶת), which literally means the part of a plant containing grains, such as an ear of corn or a stalk of grain or, in different contexts, "stream, torrent". The modern use derives from an account in the Hebrew Bible, in which pronunciation of this word was used to distinguish Ephraimites, whose dialect lacked a /ʃ/ phoneme (as in shoe), from Gileadites, whose dialect did include such a phoneme.

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