acrosomal cap(redirected from acrosomal head cap)
A caplike organelle or saccule derived from Golgi elements that surround the anterior two thirds of the nucleus of a sperm. Enzymes contained within this structure probably facilitate the sperm's penetration of the zona pellucida of the oocyte.
[acro- + G. soma, body]
ac·ro·so·mal cap(ak'rō-sō'măl kap)
A collapsed caplike membranous vesicle that covers the anterior part of the nucleus of a spermatid, derived from the acrosomal granule.