Taw, Tav or Taf is the twenty-second and last letter in many Semitic abjads, including Phoenician, Aramaic, Hebrew Taw (Modern Hebrew: Tav) ת and Arabic alphabet Tāʾ ت (look below). Its original sound value is /t/.

The Phoenician letter gave rise to the Greek Tau (Τ), Latin T, and Cyrillic Т.

Taf is said to have come from a mark; or asterisk-like marking, perhaps indicating a signature.

Its literal usage in the Torah denotes a wound ; or in modern semantics, carving into a canvas.

Hebrew spelling: תָו

The letter Tav in modern Hebrew usually represents a voiceless alveolar plosive /t/).

The letter Tav is one of the six letters which can receive a Dagesh Kal. The six are Bet, Gimmel, Daled, Kaph, Pe, and Tav (see Hebrew Alphabet for more about these letters). Three of them (Bet, Kaph, and Pe) have their sound values changed in modern Hebrew from the fricative to the plosive by adding a dagesh. The other three have the same pronunciation in modern Hebrew but have had alternate pronunciations at other times and places. In traditional Ashkenazi pronunciation, Tav represented an /s/ (a form which is still heard today, especially among Diaspora Jews) without the dagesh, and had the plosive form when it had the dagesh. In some Sephardi areas, some Chassidic groups, as well as Yemen, Tav without a dagesh represented a voiceless dental fricative /θ/ without a dagesh and the plosive form with the dagesh. See Bet, Daled, Kaph, Pe, and Gimmel.