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(ŭn-bī′ăst) 1. Neutral; impartial; uninfluenced. 2. Scientifically randomized.


(ŭn-bŭnd′ling) Separately billing for laboratory tests or procedures that are normally linked in order to extract more money from a payer (such as Medicare). This practice is illegal in the U.S.


(ŭng′kăl) Pert. to the uncus of the brain.

uncal herniation

Transtentorial herniation.


(ŭng″kar′ē-ă) [L. uncus, hook] A genus of tropical Asian woody vines.

U. tomentosa A species used medicinally for its extracts, which include alkaloids used as an anti-inflammatory for arthritis and also for their effects on thinking, concentration, and sedation. It has also been promoted as a treatment for AIDS but without scientific validation. SYN: cat’s claw; U. guianensis.

unciform, unciforme

(ŭn′sĭ-form″) [uncus + -form] Uncinate.


(ŭn′sĭ-nāt″) [L. uncinatus, hooked] Hook-shaped; hooked. SYN: unciform.

uncinate bundle of Russell

(ŭn′sĭ-nāt″) [James S. Risien Russell, Brit. physician, 1863–1939] Fibers that arise in the fastigial superior cerebellar peduncle and pass inferiorly to the vestibular nuclei and reticular formation by which impulses are carried to muscles, esp. those of the neck and body.


(ŭn-kōt′ĭng) The release of viral nucleic acids from the capsid that covers them. Uncoating of viruses can be complete or incomplete and can occur before a virus enters the cell or after it penetrates a cell membrane.

uncombable hair syndrome

(ŭn-kōm′ă-bĕl) A rare disorder, typically identified in childhood, in which hair grows in unruly bundles (“spun glass arrangement”). The hair is dry, shiny, or blond, and easily broken. A cross section often reveals a triangular or grooved shaft. The condition is often associated with other birth defects. SYN: spun glass hair syndrome. SEE: pili trianguli et canaliculi.


(ŭn-kom′plĕ-men″tĕd) Not joined or associated with complement and thus inactive.


(ŭn-kŏn-sĕrn′) Profound lack of interest or nonchalance disproportionate to societal norms. It is a characteristic of some brain diseases, including certain forms of brain injury, dementias, intoxications, and strokes.


(ŭn-kon′shŭs) 1. Lacking in awareness of the environment; insensible. SEE: unconsciousness. 2. In Freudian psychiatry, that part of the mind that consists of unrecognized feelings and drives.

personal u. In Jungian psychology, one of two divisions of the unconscious, comprising all of the material acquired through one’s own personal experience and stored in one’s own unconscious. SEE: sociobiology.


(ŭn″kon′chŭs-nĕs) The state of ...

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