Kerckring folds

cir·cu·lar folds of small intestine

[TA]
the numerous folds of the mucous membrane of the small intestine, running transversely for about two thirds of the circumference of the gut.

cir·cu·lar folds of small in·tes·tine

(sĭr'kyū-lăr fōldz smawl in-tes'tin) [TA]
The numerous folds of the mucous membrane of the small intestine, running transversely for about two thirds of the circumference of the gut.
Synonym(s): plicae circulares intestini tenuis [TA] , Kerckring folds, Kerckring valves.

Kerckring folds

mucosal folds in the human small intestine which greatly increase the absorptive surface area of the organ.