Samekh or Simketh is the fifteenth letter in many Semitic alphabets, including Phoenician, Hebrew, and Aramaic, representing . The Arabic alphabet, however, uses a letter based on Phoenician šin to represent (see there).
The Phoenician letter gave rise to the Greek Chi (Χ) and Xi (Ξ), and Latin X.
Samekh and Mem form the abbreviation for the Angel of Death, whose name in Hebrew is Samael. It also stands for centimetre.
Samekh is said to have been the miracle of the Ten Commandments. records that the tablets "were written on both their sides." The Talmud (tractate Shabbat 104a) explains that there were miracles involved with the carving on the tablets. One was that the carving went the full thickness of the tablets. The stone in the center part of the letter Samekh should have fallen out, as it was not connected to the rest of the tablet, but it did not; it miraculously remained in place. Scholars disagree, as the Ten Commandments would have been written in the style of the period, and thus Samekh would have been similar to the Phoenician pictogram seen in the table. Ayin, however, would have been the subject of this miracle, as its ancient form was similar to the modern day Samekh.
ס | Samek (lizherenn) | Samech | Sámej | Samech (lettre) | ס | Samech | Sameh