Begadkefat

Begadkefat (also begadkephat, begedkefet) is the name given to a phenomenon of lenition affecting the non-emphatic stop consonants of Biblical Hebrew and Aramaic when they are preceded by a vowel and not geminated. The name is also given to similar cases of spirantization of post-vocalic plosives in other languages; for instance, in the Berber language of Djerba.Irish has a similar system.

The phenomenon is attributed to the following consonants:

The name of the phenomenon is made up with these six consonants, mixed with haphazard vowels for the sake of pronunciation: BeGaDKePaT. The Hebrew term בֶּגֶ״ד כֶּפֶ״ת‎ (Modern Hebrew /ˌbeɡedˈkefet/) denotes the letters themselves (rather than the phenomenon of spirantization).

Begedkefet spirantization developed sometime during the lifetime of Biblical Hebrew under the influence of Aramaic. Its time of emergence can be found by noting that the Old Aramaic phonemes /θ/, /ð/ disappeared in the 7th century BC. It persisted in Hebrew until the 2nd century CE. During this period all six plosive / fricative pairs were allophonic.

In Modern Hebrew three of the six letters, ב‎ (bet), כ‎ (kaf) and פ‎ (pe) each still denote a stop–fricative variant pair; these variants are, however, no longer purely allophonic (see below). Although orthographic variants of ג‎ (gimel), ד‎ (dalet) and ת‎ (tav) still exist, these letters' pronunciation always remains acoustically and phonologically indistinguishable. In Yiddish, ת‎ can denote a fricative variant, [s].

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