Is it farther or further?
spermatozoon sper·mat·o·zo·on (spər-māt'ə-zō'ŏn', -ən, spûr'mə-tə-)
n. pl. sper·mat·o·zo·a (-zō'ə)
The mature male gamete or sex cell that consists of a cylindrical nucleated cell with a short neck and a thin motile tail, contains genetic information to be transmitted by the male, exhibits autokinesia, and is able to effect zygosis with an ovum; sperm.