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(hī″pĕr-rĕz′ō-năns) [″ + L. resonare, to resound] An increased resonance produced when an area is percussed.


(hī″pĕr-săl″ĭ-vā′shŭn) [″ + L. salivatio, salivation] Ptyalism.


(hī″pĕr-si-krē′shŏn) [hyper- + secretion] The excessive release of a substance by a cell, gland, tissue, or organism.


(hī″pĕr-sĕn′sĭ-bĭl′ĭ-tē) [″ + L. sensibilitas, sensibility] Hypersensitivity.


(hī″pĕr-sĕn′sĭ-tĭv) [″ + ″] Excessively and abnormally susceptible to a stimulus, e.g., an antigen like pollen. SYN: supersensitive. SEE: allergy; anaphylaxis; hay fever.


(hī″pĕr-sĕn″sĭ-tĭv′ĭ-tē) An abnormal sensitivity to a stimulus of any kind.

visceral h. An abnormally low tolerance for painful stimuli in the internal organs. It is seen, e.g., in patients with irritable bowel syndrome.

hypersensitivity reaction



(hī″pĕr-sĕn″sĭ-tĭ-zā′shŭn) 1. Producing or inducing increased sensitivity to an organism or drug. 2. The condition of being highly sensitive to something.


(hī″pĕr-som′nē-ă) [hyper- + (in)somnia] 1. Excessive daytime sleepiness resulting from any cause, e.g., inadequate sleep hygiene, the use of intoxicating drugs, or obstructive sleep apnea. 2. Excessive daytime sleepiness lasting more than 1 hr every day for several months; the inability to feel refreshed after sleeping; excessively long periods of sleep (total sleep time of more than 10 hr a day); no evidence of cataplexy or narcolepsy. SYN: idiopathic.

idiopathic h. Hypersomnia.

recurrent h. Excessive sleepiness that occurs periodically, e.g., every few weeks or months.

traumatic h. Excessive sleepiness in patients with traumatic brain injury.


(hī″ pĕr-splĕn′ ĭzm) Increased sequestration of blood cells by the spleen.


(hī″pĕr-sthĕn′ĭk) 1. Denoting excessive strength or tension. 2. Denoting a body habitus characterized by a broad, deep thorax, short thoracic cavity, and a large abdominal cavity; a massive build.


(hī″pĕr-sŭ-sĕp″tĭ-bĭl′ĭ-tē) [″ + ″] An exaggerated susceptibility to an antigen, chemical, disease, or other stimulus.


(hī″pĕr-tĕl′or-ĭzm) [″ + telouros, distant] Abnormal distance between two paired organs, esp. the eyes.


(hī″pĕr-ten′shŏn) [hyper- + tension] ABBR: HTN. In adults, a condition in which the blood pressure (BP) is higher than 140 mm Hg systolic or 90 mm Hg diastolic on three separate readings recorded several weeks apart. Hypertension is one of the major risk factors for coronary artery disease, heart failure, stroke, peripheral vascular disease, kidney failure, and retinopathy. It ...

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