A muscle which surrounds, and by its contraction tends to close, a natural opening; as, the sphincter of the bladder.
Of, pertaining to, or designating, a sphincter; as, a sphincter muscle.
A ring of muscle surrounding a bodily orifice opening, such as the anus and urethra
A valve found in, or at the end of, some tubes of the body. They contain a ring of muscle that can open or close the valve, and therefore control the flow of materials along the tube.
Ring of muscle that closes off a tube in the body, such as at the base of the food pipe or the neck of the bladder
a ring of muscle fibers located around a naturally occurring passage or opening in the body that opens and closes to regulate passage of substances
A ring of muscle around a natural opening or passage that acts like a valve, controlling inflow or outflow.
Smooth-muscle ring that surrounds a tube, closing tube as muscle contracts.
Smooth muscle ring that, when contracted, closes off a part of the GIT or blood vessel.
(n) a circular muscle constricting an orifice. Examples are the cardiac sphincter, located between the esophagus and the stomach; the pyloric sphincter, between the stomach and the small intestines; and the ileocecal valve, between the small intestine (ileum) and the colon (cecum).
Greek sphinkter = a tight binder; hence, a circular muscle which closes an orifice; adjective - sphincteric.
Circular band or ring of muscle that serves to open or close a tube or orifice; analogous to a valve.
a ring of muscle that controls an opening
A ringlike band of muscle that constricts a passage or closes a natural orifice. Examples include esophageal sphincters and the anal sphincter.
Group of muscles surrounding an opening in the body that expand or contract to control the flow of fluid through the opening. The urinary sphincter at the base of the bladder controls urine flow through the urethra.
sphinkter = a binder, from sphingo = I strangle; a ring-like muscle controlling an aperture.
Muscular structure that surrounds the urethra and allows the bladder to store or empty urine. This muscle is circular and acts like a valve, can relax or tighten to open or close the outlet of the bladder. The urethra has an internal and external sphincter. Internal sphincter is the portion of the urethra found at the bladder neck that keeps the urethra closed when a person is at rest. External sphincter is the portion of the urethra that is under a person's own control (voluntary control). The external sphincter is able top stop the flow of urine during voiding.
(sfingk´ ter) [Gr. sphinkter: that which binds tight] • A ring of muscle that can close an orifice, for example at the anus.
A ring-shaped muscle that surrounds a natural opening in the body and can open or close it by relaxing or contracting.
The valve just below the prostate which allows continence
the ring-like muscle that maintains constriction of a body passage or orifice and that relaxes by normal physiological functioning(e.g. the sphincter controls urination and keeps us dry between urinations). In the bladder exstrophy population(those patients with bladder exstrophy, cloacal exstrophy, and complete epispadias), there is no development of the urinary sphincter and thus, even after closure of the bladder or urethra, or both, there is still dripping of urine from the urethra. A sphincter has to be constructed from bladder muscle in order for the child to be rendered dry of urine.
A small muscle that can open or block a passageway, such as the urethra or the rectum.
a ring of muscle that contracts to close an opening
a circular muscle that constricts and expands
a circular muscle that opens and closes like a door
a mass of circular muscle that constricts to close the lumen, and prevent peristaltic movement of food
a muscle that forms a circle around a natural passageway in the body
an entrance to a cavity that can open and close, controlling the flow of organic matter in the alimentary canal
a ring-like muscle that normally maintains constriction of a natural body passage or orifice and that relaxes as required by normal physiological functioning
a ring-like muscle which opens and closes a natural orifice
a ring of muscle around a natural opening or passage that acts like a valve, regulating inflow and outflow
a ring of muscle that contracts to close off a passage or opening in the body
Circular muscle which closes off a hollow organ during contraction.
A band of muscle fibers that can relax or tighten to open or close a bodily opening or passage.
(G. sphinkter, that which binds tight), E.g., sphincter ani.
A ring-like muscle which closes a passage, i.e: around the urethra.
A sphincter muscle surrounds the urethra, holding it closed until it is time to urinate.
A ring like band of muscle fibres that constricts a passage or closes a natural orifice; called also musculus sphincter.
A ringlike band of muscle that constricts a passage or closes a natural body opening.
A muscular valve.
ring-like muscle which opens and closes voluntarily. The sphincter in the anus provides bowel control and the bladder sphincter controls urine.
Circular muscle that tightens and relaxes to control the flow of urine from the urethra. There are internal and external urethral and anal sphincters.
an accumulation of specially arranged fibers, the function of which is to partially or totally reduce the opening of tubular structure
muscles around the urethra that are used to open and close it.
Muscle at the bottom of the bladder that acts like a gate to hold urine in. The brain sends messages to muscle to open or to stay closed at the right time.
A circular muscle that acts as the mechanism to close the urethra when voiding is not desired.
Muscles that form a ring around the orifice of the anus.
a circular muscle that opens and closes at an entrance to an organ. Examples include the lower esophageal sphincter and the anal sphincter.
A ring-shaped muscle that relaxes or tightens to open or close a passage or opening in the body. Examples are the anal sphincter (around the opening of the anus) and the pyloric sphincter (at the lower opening of the stomach).
circular muscle at base of bladder neck and also around the anus, which controls opening of the bladder and bowel respectively.
A muscular fiber responsible for reduction or obliteration of the lumen to prevent the flow of urine in the ureter.
A ring-shaped muscle that closes an opening, such as the sphincter muscles in the lower end of a cow's teat.
ring-like band of muscle that opens and closes an opening in the body.
a muscle that controls the opening of a duct or orifice (e.g., anal sphincter).
The internal and external muscle that surrounds the anus. The sphincter permits continence or control over intestinal function.
A ring of muscle fibers located around an opening in the body that regulates the passage of substances.
anal or urethral muscle that closes to prevent passage of urine or feces.
The urinary sphincter controls the flow of urine and is located in the area of the bladder neck and urethra. It opens when the bladder is full and shuts when the bladder is empty.
A ring like muscle surrounding and able to contract and close a bodily opening.
A circular muscle which contracts to close an orifice. The urethral sphincter squeezes the urethra shut, providing urinary control.
(sfingk-ter) - A round muscle that opens and closes to let urine out of the bladder when it is time to urinate
A ring-like band of muscle fibers that closes a natural opening. Tightening the urethral sphincter controls the urge to urinate. Tightening can also prevent loss of urine and can serve as a reflex mechanism to calm the bladder and relax the detrusor muscle. Both the anus and the urethra have sphincters, whose muscle tone is key to preventing leakage and maintaining fecal and urinary continence, respectively.
Circular muscle that constricts to close and relaxes to open a passageway.
A circular band of muscle that can relax and contract to open and close like a tap.
Muscle at the base of the bladder that acts like a gate to hold urine in. Brain sends message to muscle to open when bladder is full or to stay closed until the child wakes up, so that he/she can use the toilet.
circular muscle surrounding an opening in the body
A muscle that surrounds an orifice
a ringlike muscle which controls opening and closing of a bodily opening
A round muscle that opens and closes to let fluid or other matter pass into or out of an organ. Sphincter muscles keep the bladder closed until it is time to urinate.
Circular muscle often found within tubular structures of the body. Relaxation or contraction of a sphincter allows controlled passage of material through the sphincter or vice versa. The sphincters of the urethra and anus work in much the same fashion.
A muscular ring that contracts to close the entrance or exit of an internal passageway.
A ring of muscle that narrows or closes off a passageway by contracting.
A band of tissue that acts like a one-way valve, allowing substances in the body to flow in one direction.
A ring of smooth muscle that can close off a tubular structure such as an arteriole or part of the colon.
A circular muscle that controls openings. There are sphincter muscles in the stomach, bowel and bladder.
A circular band of muscle that surrounds and is capable of closing off an opening to one of the bodyâ€(tm)s hollow organs (see Urinary Incontinence).
A circular band of muscle fibers that constricts or closes a passage or opening.
A sphincter is a stracture, usually a circular muscle which normally maintains constriction of a natural body passage or orifice and which relaxes as required by normal physiological functioning. There are at least 42 different sphincters in the human body, some of them microscopic in size.