亀き頭とう球きゅう

noun

bulbus glandis; knot (of a canid penis)

Anatomical term for the bulbous structure at the base of the glans in canids and some other mammals, often referred to as the 'knot' in breeding contexts.

• 犬いぬの交こう尾びの際さい、亀き頭とう球きゅうが膨ぼう張ちょうして結けつ合ごうが維い持じされる。

  During canine mating, the bulbus glandis swells to maintain the tie.