1911 Encyclopædia Britannica/Zero

ZERO, the figure 0 in the Arabic notation for numbers, nought, cipher. The Arabic name for the figure was sifr, which meant literally an empty thing. The old Latin writers on arithmetic translated or transliterated the Arabic word as zephyrum; this in Ital. became zefiro, contracted to zero, borrowed by F. zéro, whence it came late into English. The Spanish form cifra, more closely resembling the original Arabic, gave O. Fr. cifre, mod. chiffre, also used in the sense of monogram, and English “cipher” which is thus a doublet. In physics, the term is applied to a point with which phenomena are quantitatively compared, especially to a point of a graduated instrument between a positive and negative or ascending and descending scale, as in the scales of temperature.