Taaf is the twenty-second and last letter of the Samaritan alphabet and carries the numeral value four hundred, the highest any single letter in the sequence holds. It writes a plain t, as against the emphatic t written by tit. The name is the inherited Northwest Semitic one behind Hebrew tav.
Its grammatical work is substantial. Taaf prefixes the second person of the imperfect verb and the third person feminine, marks the feminine in a wide range of nouns and adjectives, and appears in several verbal patterns as an added element. Few letters in the alphabet turn up in more different grammatical roles.
The gloss on its name is a mark, and unlike most of the glosses in this alphabet it has an unusually long tail behind it. In the earliest Semitic writing the sign in this position was drawn as a cross, and a letter that is last in the alphabet, that is named a mark, and that is shaped like a cross accumulated symbolic weight in more than one later tradition on the strength of those three facts together. The gloss remains a reconstruction. What is not reconstructed is that the sign was so drawn and that the association was made.
Greek took it as tau and Latin as T. In the Semitic alphabets it closes the sequence; in Greek and Latin it does not, because both added letters of their own behind it.
The character is encoded at U+0815, the last letter in the block.