Shibboleth,
n.
river, or an ear of corn. The tribes living on the east of Jordan, separated
from their brethren on the west by the deep ravines and the rapid river,
gradually came to adopt peculiar customs, and from mixing largely with the
Moabites, Ishmaelites, and Ammonites to pronounce certain letters in such a
manner as to distinguish them from the other tribes. Thus when the Ephraimites
from the west invaded Gilead, and were defeated by the Gileadites under the
leadership of Jephthah, and tried to escape by the "passages of the Jordan,"
the Gileadites seized the fords and would allow none to pass who could not
pronounce "shibboleth" with a strong aspirate. This the fugitives were unable
to do. They said "sibboleth," as the word was pronounced by the tribes on the
west, and thus they were detected (Judg. 12:1-6).
Source: Easton's 1897 Bible Dictionary (via Dictionary.com)
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