sper·mat·o·zo·on 
(spər-măt′ə-zōŏn′, -ən, spûr′mə-tə-)
(spər-măt′ə-zōŏn′, -ən, spûr′mə-tə-)n. pl. sper·mat·o·zo·a (-zōə)
The mature male gamete of an animal, usually consisting of a nucleate head, a short neck, and a thin motile tail.
sper·mat′o·zoal (-zōəl), sper·mat′o·zoan (-zōən), sper·mat′o·zoic (-zōĭk) adj.