lactiferous sinus

(redirected from ampulla of lactiferous duct)

lac·tif·er·ous si·nus

[TA]
a circumscribed spindle-shaped dilation of the lactiferous duct just before it enters the nipple. In nursing mothers, this dilation stores a droplet of milk that is expressed by compression as the infant begins to suckle; this is thought to encourage continual suckling while the let-down reflex ensues.

lac·tif·er·ous si·nus

(lak-tif'ĕr-ŭs sī'nŭs) [TA]
A circumscribed spindle-shaped dilation of the lactiferous duct just before it enters the nipple. In nursing mothers this dilation stores a droplet of milk that is expressed by compression as the infant begins to suckle; this is thought to encourage continual suckling while the let-down reflex ensues.

lactiferous sinus

Immediately inside the tip of the nipple, the dilated end of any of the 15-20 lactiferous ducts, which convey milk from the mammary glands during lactation.
See also: sinus

lactiferous

conveying milk.

lactiferous ducts
appearing first as epithelial diverticula which invade the mammary mesenchyme from the mammary buds, the precursors of the teats, these solid cords of cells later cavitate to produce lactiferous ducts.
lactiferous sinus
large cavity, continuous with the lactiferous ducts in mammary tissue, which serves as a reservoir for accumulated milk in the mammary gland until it is released at milking or suckling via the teat sinus and teat canal; is a combination of gland and teat sinuses.