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Related to Urination: Frequent urination


The discharge of urine from the bladder. Also known as micturition.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(also called micturition), the reflex act of excreting urine from the body.

Uropoiesis—the production of urine—is a constant process, but urination occurs only intermittently, as the urinary bladder fills. Humans urinate four to six times daily. Urine is prevented from escaping from the bladder by two ring-shaped layers of muscle fibers: an internal sphincter, which consists of smooth muscle fibers, and an external one, which consists of striated fibers. When the pressure within the bladder reaches 2–2.66 kN/m2 (kilonewtons per square meter), or 15–20 mm Hg (millimeters of mercury), stimulation of the mechanoreceptors (the nerve endings of sensory neurons) in the wall of the bladder elicits the urge to urinate. In man, this critical pressure is achieved when 300–350 ml of urine accumulate in the bladder. During urination, the external sphincter relaxes reflexively as the muscles of the bladder wall contract.

Urination is regulated by the nerve centers in the spinal cord and brain; these centers are controlled, in turn, by the cerebral cortex. The filling of the urinary bladder arouses the cerebral cortex to elicit the urge to urinate. Certain neurological diseases, as well as injuries to the muscles of the urinary bladder, impair urination.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

What does it mean when you dream about urination?

Urination in a dream has several interpretations that range from inhibited sexual desires to the outpouring of emotional feelings that have been repressed.

The Dream Encyclopedia, Second Edition © 2009 Visible Ink Press®. All rights reserved.


Releasing bodily wastes in a dream suggests a need to release repressed emotions and/or anxiety. At times, urination may have sexual connotations. Many people dream about the need to urinate, which wakes them up, and then they realize that they need to use the bathroom. At times, the dream triggers the physical sensation and other times the physical sensation may become a part of the dream.
Bedside Dream Dictionary by Silvana Amar Copyright © 2007 by Skyhorse Publishing, Inc.
References in periodicals archive ?
Given the potential health issues associated with nocturia, be sure to inform your doctor about any problems you're having with nighttime urination, especially if they're affecting your quality of life, Dr.
Damaged kidneys are not able to filter and/or concentrate urine properly, which can lead to increased urination and increased risk for leakage.
For patients with BPH and OAB, the key of medication treatment was increasing urinary bladder pressure and contraction of bladder to promote urination, inhibiting bladder contraction, reducing afferent sensation to improve storage symptoms.
Right-sided renal colic with haematuria and strangury, and frequent ineffectual urging for urination with dribbling of urine are common pointers to Nux vomica, particularly in thin, irritable, and nervous people.
Although these trials showed a small reduction in the average number of night-time urinations with Noctiva compared to placebo, more patients treated with Noctiva were able to at least halve their number of night-time urinations, and patients treated with Noctiva had more nights with one or fewer night-time urinations.
The frequency of nighttime urination (FNU) was counted to assess the changes in overnight urine output.
Urination status before and after continuous positive airways pressure treatment Before CPAP After CPAP p value Nocturia (times) 1.4 [+ or -] 1.3 0.7 [+ or -] 0.9 <0.01 IPSS Total score 6.0 [+ or -] 6.4 4.3 [+ or -] 5.1 <0.01 Voiding score 2.9 [+ or -] 4.2 2.3 [+ or -] 3.5 <0.01 Storage score 3.1 [+ or -] 2.9 2.0 [+ or -] 2.1 <0.01 OABSS score 2.7 [+ or -] 2.6 1.7 [+ or -] 1.7 <0.01 Patients with urgent 12 6 incontinence CPAP: continuous positive airways pressure; IPSS: International Prostate Symptom Score; OABSS: Overactive Bladder Symptom Score.
One victim of a "public urination notice" was a mum whose two-year-old needed to use his potty while out shopping.
Mary is a 13-year-old thin female being seen for complaints of frequent urination, hunger, and excessive thirst.
"Diabetes signs and symptoms can include severe thirst, frequent urination, impaired sensation, delayed healing of wounds, weight changes, blurred vision and fatigue.
Leandra A Some dogs urinate when they are approached or petted; this is called submissive urination. Others urinate when they are excited and seem alert and happy; this is called excitement urination.