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(gŭt′ŭ-răl) [L. gutturalis, pert. to the throat] Pert. to the throat.

Guyon, Felix J.C.

(gē-yōn′) Fr. surgeon, 1831–1920.

G. canal A tunnel on the ulnar side of the wrist formed by the hook of the hamate and pisiform bones. The ulnar nerve may be compressed at this site in long-distance bicyclists, by falling on the wrist, or by repetitive wrist actions.

G. sign Ballottement of the kidney.


graft-versus-host disease.


gray (unit of measurement of radiation).


(jim-nas′tiks) [Gr. gymnastikos, pert. to a gymnasium] Systematic body exercise with or without special apparatus.


(jim-nē′mă) [Gr. gymnos, naked + nēma, thread] A genus of climbing perennial shrubs native to the East Indian Archipelago (Indonesia). Extracts of some species are used in alternative medicine.

G. sylvestre A species used in Ayurvedic medicine as a treatment for diabetes mellitus. SYN: gurmar.


SEE: gyneco-.

gyneco-, gynec-

[Gr. gynē, stem gynaik-, woman] Prefixes meaning woman, female, female reproduction. The variant gynaeco- is used outside the U.S.

gynecologic, gynecological

(gī″nĕ-kŏ-loj′ ĭk, jī″, jin″ĕ-, gī″nĕ-kŏ-loj′ĭ-kăl, jī″, jin″ĕ-) [gyneco- + -logy] Pert. to gynecology.


(gīn″ĕ-kol′ŏ-jĭst, jin″ĕ-kol′ŏ-jĭst) A physician who specializes in gynecology.


(gī″nĕ-kol′ŏ-jē, jin″ĕ-kol′ŏ-jē) [gyneco- + -logy] The study of women’s health care, esp. diseases and conditions that affect reproduction and the female reproductive organs. gynecologic, adj. gynecological, adj.


(jī″nĕ-kō-mas′tē-ă, gī″nĕ-kō-mas′tē-ă, jin″ĕ-kō-mas′tē-ă) [gyneco- + masto- + -ia] Enlargement of breast tissue in the male. This may occur during three distinct age periods: transiently at birth, again beginning with puberty and declining during the late teenage years, and finally in adults over age 50 years. In the newborn, it is caused by stimulation from maternal hormones. A milky secretion (“witch’s milk”) may be produced; the condition disappears within a few weeks. During middle adolescence, as many as 60% of boys may develop some degree of gynecomastia, either unilateral or bilateral and, if bilateral, often with varying degrees of growth between the two sides. It may be produced by the use of alcohol, marijuana, and heroin, but it is often a normal, nonpathological condition and usually disappears within 18 months. Hormonal assays should be performed only if the condition appears before puberty, persists longer than 2 years, or is associated with other signs of endocrine disorders. In older men, the condition can be caused by pituitary ...

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