Oliguria

n. scarcity of urine secretion in relation to the intake of fluids into the body (Medicine)

Oliguria and anuria are the decreased or absent production of urine, respectively. The decreased production of urine may be a sign of dehydration, renal failure or urinary obstruction/urinary retention.
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Oliguria /ol·i·gu·ria/ diminished urine production and excretion in relation to fluid intake.oligu´ric ol·i·gu·ri·a n. [more]Oliguria - Community and Resources

Noun
1. abnormally small production of urine; can be a symptom of kidney disease or obstruction of the urinary tract or edema or an imbalance of fluids and electrolytes in the body
(hypernym) symptom
2. production of an abnormally small amount of urine
(hypernym) micturition, urination

Less urination than normal.