This is how Aryabhata’s “Ardh-Jya” became “Sine”

Aryabhata discussed the concept of sine in his work by the name of ardha-jya. Literally, it means “half-chord“. For simplicity, people started calling it jya. When Arabic writers translated his works from Sanskrit into Arabic, they referred it as jiba.

However, in Arabic writings, vowels are omitted, and it was abbreviated as jb.

Later writers substituted it with jiab, meaning “cove” or “bay” (in Arabic, jiba is a meaningless word).

Later in the 12th century, when Gherardo of Cremona translated these writings from Arabic into Latin, he replaced the Arabic jiab with its Latin counterpart, sinus, which means “cove” or “bay”. And after that, the sinus became sine in English.

Related Posts: Does no one remember the Hindu contribution to Mathematics? and Does no one remember Indian Contribution to Mathematics – Part 2

Source: Howard Eves (1990). An Introduction to the History of Mathematics (6 ed.). Saunders College Publishing House, New York. p. 237; Image of Sine Angle: Courtesy Wikipedia