sifir = zero. This is the same etymology as the English word "cypher", which originally meant zero as well, but became associated with codes and secrecy because Hindu-Arabic numerals were not understood by most people in Europe and used to send secret messages. One of the main things that set Hindu-Arabic numerals apart from Roman numerals is the inclusion of a symbol for zero, so this was the number that gave its name to the codes.
Sorry, i just think that's interesting :-)
sıfır comes from the Arabic word "sif'r صفر" meaning empty, the indian word for zero is "शून्य shoony". The word zero came into the English language via French zéro from Italian zero, Italian contraction of Venetian zevero form of 'Italian zefiro.The Italian mathematician Fibonacci (c. 1170–1250), who grew up in North Africa and is credited with introducing the decimal system to Europe, used the term zephyrum. This became zefiro in Italian, and was then contracted to zero in Venetian. The Italian word zefiro was already in existence (meaning "west wind" from Latin and Greek zephyrus) and may have influenced the spelling when transcribing Arabic "sif'r".
I never knew the word was associated with cypher, that's really cool. I knew that it was from Arabic meaning 0 because I've seen it in other languages I've learned a little of (Persian and Swahili for example) but now I'm putting all this information together. Have a lingot for your cool insight!