vas rectum

(somewhat dated) A straight seminiferous tubule conveying semen from its pertaining tubulus seminiferus contortus (convoluted seminiferous tubule) to the rete testis of the testicle that contains it; now more commonly called the tubulus seminiferus rectus (straight seminiferous tubule).

(sometimes more fully, “vas rectum renis”) Any one of many straight capillaries in the kidney that branch off from the arteriolae efferentes (efferent arterioles) of juxtamedullary nephrons, enter the medulla, and surround the loop of Henle, where they function to absorb water and to secrete salt and urea into the renal interstitium, thereby facilitating the production of concentrated urine.

Any one of numerous straight arteries that branch off from the arcades of the mesentery of the jejunum and ileum whence they head toward the small intestine.