Qoph or Qop (In Modern Hebrew: Kuf/Kof, Arabic: Qāf) is the nineteenth letter in many Semitic abjads, including Phoenician, Aramaic, Syriac, Hebrew ק and Arabic alphabet qāf ق (in abjadi order). Its sound value is an emphatic [kˤ] or [q]. The OHED (Oxford Hebrew English Dictionary) gives the letter Qoph a transliteration value of Q or a K and a final transliteration value as a ck. In Hebrew Gematria, it has the numerical value of 100.

It became over time the letter qima in certain ancient varieties of the Coptic alphabet (which is itself an evolution of the ancient Greek alphabet), later added back into the ancient Greek alphabet itself as the ancien letter qoppa (looking more like the Phoenician letter qoph), and finally the letter Q in the Latin alphabet from the ancient Coptic-Greek qima or qoppa (after Coptic texts were translated into Greek and Latin by Coptic scribes, to preserve the Coptic distinction with the sound /k/ for which they used another older koppa form of the classical Greek kappa letter).