Medical Definition of Sperm

Sperm: A sperm is the male "gamete" or sex cell. It combines with the female "gamete," called an ovum, to form a zygote. The formation process is called "fertilization." (see ovum, zygote).

Source: MedTerms™ Medical Dictionary
http://www.medicinenet.com/script/main/art.asp?articlekey=5524
Last Editorial Review: 5/13/2016