An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A → cardinal number between → six and → eight.

From M.E. seoven(e), seofne, seven, O.E. seofon, cognate with M.Du. seven, Du. zeven, O.H.G. sibun, Ger. sieben, related to Pers. haft, as below, from PIE *septm "seven."

Haft, from Mid.Pers. haft, Av. hapta Skt. sapta, Gk. hepta, L. septem.