am'plitude. 1

In physics, the distance between the extreme limits of a'n oscillation or vibration. Thus, the a. of vibration of a pendulum is the chord of the arc through which it oscillates; the a. of vibration of a wave is the distance from the crest to the trough of the wave. 2. Of the pulse, its fullne , i. e., the extent of dilatation of the artery at each impulse of the heart. [Lat., amplitudo.] ampule (am-pul')- A small bottle or flask, usually sealed hermetically; used for preparations which must be kept aseptically or without exposure to air. [Fr., ampoule.} AMYELUS ampul'la. 1. In chemistry and physics, a gla flask with long neck and dilated body or a small hollow gla globe. 2. In anatomy, a flask like expanded portion of a canal. 3. In pathology (rarely used), a bleb or blister, a. canaliculi lacrimal is. A dilatation at the curvature of the lacrimal canal, a. chyli, a. chylifera. See receptaculum chyli. a. duct us lactiferi. A sinus of the mammary gland, being the expanded portion of a milk duct near the nipple, serving as a kind of temporary reservoir for the milk. a. Fallopii tubae. The outer, sinuous dilated portion of the oviduct. a. membranacea labyrinth i. That portion of the membranous labyrinth of the ear which is inclosed in the a. of a semicircular canal. a. nervi optic i. The dilatation of the sub vaginal space of the optic nerve at its anterior extremity. a. of the rectum. That portion which is situated between the muscular floor of the above;pelvis closed below in and the the "third normal sphincter" condition by the collapse, a. of the vagina. The dilatable upper portion of the vagina. a. of the vas deferens. A saccular enlargement near the termination of the canal beneath the bladder, a. of Vater. A small cavity in the wall of the duodenum, between the muscular and mucous layers, into which the duct us choledochus and the pancreatic duct empty independently; described by Vater, a Dutch anatomist, a. o ea. The dilated portion of an o eous semicircular canal of the ear at its union with the vestibule, serving for the lodgment of the a. membranacea. L/ieberkiihn's a. The cecal end of a lacteal in an intestinal villus. [Lat., ampulla, flask.]