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(lă-sĕrt′ŭs) [L. lacertus, lizard] 1. The muscular part of the arm. 2. A muscular or fibrous band.

Lachesis muta

(lak′ĕ-sĭs mū′t ă) SEE: bushmaster.

Lachman test

(lok″măn) [John Lachman, contemporary U.S. orthopedic surgeon] A test to evaluate the integrity of the anterior cruciate ligament of the knee. The examiner stands on the side being examined and grasps the tibia at the level of the tibial tubercle while stabilizing the femur with the other hand. The patient relaxes the leg while the examiner holds the knee flexed at 25° to 30° and pulls forward on the tibia while stabilizing the femur. Excessive motion relative to the opposite knee or no discernible end point determine a positive result. SEE: illus.




Biomechanics of the Lachman test for anterior cruciate laxity



(lak′ĕr) [Portuguese lacre, ult. fr Persian lâk, (tree) resin, lac] A resin or varnish that leaves a tough coating on a surface. It may be impregnated with medication, e.g., in the treatment of diseases of the toenails or fingernails.

lacrimal, lachrymal

(lak′rĭ-măl) Pert. to tears. SEE: lacrimal apparatus.

lacrimal apparatus

Structures concerned with the secretion and conduction of tears. It includes the lacrimal gland and its secretory ducts, lacrimal canaliculi, lacrimal sac, and nasolacrimal duct, which empties into the nasal cavity. SEE: illus.




Anterior view


Patency of the lacrimal duct may be tested by placing a dilute solution of sugar in the conjunctival sac; if the duct is patent, the individual will report the sensation of sweetness in the mouth; if not, the sugar will not be perceived.

lacrimation, lachrymation

(lak″rĭ-mā′shŏn) The secretion and discharge of tears; weeping.


(lakt″as′ĭd) Lactic acid.


(lakt-as″ĭ-dē′mē-ă) [lactacid + -emia] Excessive accumulation of lactic acid in the blood. It occurs normally after strenuous and prolonged exercise. SYN: lactic acidemia; lacticemia.


(lakt″as″ĭ-door′ē-ă, -dūr′) [lactacid + -uria] Lactic acid excreted in the urine.


(lak″tal″bū-mĭn) [lacto- + albumin] The albumin found in the whey portion of milk.


(lak′tam″) An organic chemical that contains the —NH—CO group in a ring form. It is formed by the removal of a molecule of water from certain amino acids.

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