Wiktionary
n. (context anatomy English) One of two simple tubular glands located behind the male urinary bladder, responsible for the production of about sixty percent of the fluid that ultimately becomes semen.
WordNet
n. adds nutrient fluid to semen during ejaculation
Wikipedia
The seminal vesicles , vesicular glands, or seminal glands, are a pair of simple tubular glands posteroinferior to the urinary bladder of some male mammals. Seminal vesicles are located within the pelvis. They secrete fluid that partly composes the semen.
Usage examples of "seminal vesicle".
This Wolffian duct can either wither away or grow into a seminal vesicle, epididymis, and vas deferens.
His entire gut seemed to gather itself for the building effort: prostate, seminal vesicle, kidneys, bladder and colon interacting to produce a potent liquid lava.