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Medical Dictionary: l

Word	Definition
L	liter
L&D	labor and delivery
L&R	left & right
lab	laboratory
labi/o	lips, labia
labial	Pertaining to the lips.
labial mucosa	The inner lining of the lips.
-labile	unstable, subject to change
labor	The childbirth process of expulsion of the fetus and placenta from the uterus.
labrum	A lip.
labyrinth	A complex system of ducts and cavities that comprise the organs of hearing and balance.
labyrinth/o	inner ear
labyrinthectomy	An ear operation used for Meniere's syndrome.
labyrinthitis	Inflammation of the inner ear (labyrinth).
laceration	A wound, specifically a deep tear or cut of the flesh.
lacrim/o	tears
lacrimation	Crying.
lact/o	milk
lactase	An enzyme secreted by the small intestine glands that convert lactose into glucose and galactose.
lactation	Production of milk by the mammary glands.
lacti-	milk
lactic acid	A organic acid produced by anaerobic respiration, by fermentation of carbohydrates in the rumen and by bacterial action on milk.
lactose	The main sugar of milk consisting of one molecule each of glucose and galactose.
lacuna	A small cavity or depression.
LAD	left anterior decending
lal/o	speech
lamella	A thin scale or plate, as of bone.
lamin/o	lamina (part of the vertebral arch that forms the roof of the spinal canal)
laminectomy	A surgical procedure to remove a portion of the vertebral bone called the lamina.
lampr/o	clear
lancet	A two-edged surgical knife with a sharp point.
lanolin	Wool fat that is refined and used as an emollient, cosmetic, and pharmaceutic aid.
lapar/o	abdominal wall
laparoscope	An endoscope for examining the abdominal and pelvic organs in the peritoneal cavity.
laparoscopy	Surgery using a thin light tube inserted into a small incision.
laparotomy	Incision into the side of the abdomen between the ribs and pelvis.
larva	Wormlike developmental stage in the life cycle of insects, worms, and other metamorphosing animals.
laryng/o	larynx
laryngectomy	Partial or total removal of the larynx.
laryngitis	Inflammation of the larynx, including the vocal cords. Characterized by voice disorders, usually viral etiology.
laryngomalacia	An abnormally underdeveloped or degenerated cartilage in the larynx.
laryngoplasty	Plastic repair of the larynx.
laryngoscopy	Visual examination of the larynx. May also include treatment.
larynx	The voice box. Includes the vocal cords and surrounding cartilage.
laser trabeculoplasty	Using a very focused beam of light to treat the drainage angle of the eye.
lat	lateral
later/o	side
lateral	Away from the body's midline
lavage	Washing out a body cavity with water or medicated solution.
laxative	Agents that produce a soft formed stool and relax the bowels, used to relieve constipation.
lb	pound
LBBB	left bundle branch block
LBW	low birth weight
LDH	lactate dehydrogenase
LDL	low-density lipoprotein
LE	lower extremity
lecith/o	yolk, ovum
leeching	The application of leeches to the body to draw blood for therapeutic purposes.
leg	The inferior part of the lower extremity between the knee and the ankle. Common usage is the entire lower limb.
-legia	reading
legionnaires disease	An acute bacterial infection of the lungs characterized by high fever, malaise, muscle aches, respiratory disorders and headache.
lei/o	smooth
leiomy/o	smooth (visceral) muscle
leiomyoma	A benign neoplasm derived from smooth muscle tissue, also known as a fibroid tumor. They usually occur in the uterus.
leiomyosarcoma	A malignant neoplasm derived from smooth muscle.
leishmaniasis	A group of infections, caused by the protozoan flagellate Leishmania.
-lemma	sheath, confining membrane
lentigo	A small, flat, pigmented spot on the skin.
lepid/o	flakes, scales
leprosy	Chronic bacterial infection that affects peripheral nerves in the hands and feet, mucous membranes of the nose, throat and eyes and that causes skin lesions.
-lepsis	seizure
-lepsy	seizure
lept-	thin, slight, slender
leptin	A hormone that regulates energy balance by helping control appetite.
lesion	Any abnormal changes or damage to body tissues.
lethargy	A condition of tiredness, fatigue, or lack of energy.
leuk/o	white
leukemia	Cancer of the blood. The bone marrow then produces abnormal white blood cells which do not function properly.
leukocyt/o	white blood cell
leukocyte	A white blood cell.
leukocytosis	An abnormally large increase in the number of leukocytes in the blood.
leukoplakia	A white patch lesion found on a mucous membrane that cannot be scraped off.
leukorrhea	Normal vaginal discharge during pregnancy . It is thin, white, milky and mild smelling.
levo-	left
levocardia	Congenital abnormalities in which the heart is in the normal position in the left side of the chest but some or all of the thorax or abdomen viscera are transposed laterally.
-lexia	reading, word
LFT	liver function test
LGI	lower gastrointestinal
LH	luteinizing hormone
Li	lithium
libido	Sexual desire.
lichen	Any of various papular skin disease in which the lesions are typically small, firm papules set very close together.
lidocaine	A local anesthetic, analgesic and cardiac depressant.
lien/o	spleen
LIF	leukemia inhibatory factor
lig	ligament
ligament	Flexible, tough bands of fibrous tissue connecting bones at a joint.
limbic	Edge.
lingu/o	tongue
lingual	Pertaining to or near the tongue.
liniments	Heat-generating liquids that are applied to the skin.
lip/o	fat, lipid
lipedema	A chronic disease that occurs mostly in females. It is characterized by bilateral, symmetrical fatty tissue excess, mainly in the legs.
lipid	Organic compounds, including the fats, oils, waxes, sterols, and triglycerides, that are insoluble in water but soluble in nonpolar organic solvents.
lipolysis	The metabolic process of breaking down of fat.
lipoma	A noncancerous growth of fatty tissue cells. Occurs over area of past trauma.
lipomatosis	A disorder characterized by abnormal tumor-like accumulations of fat in body tissues.
liposarcoma	A malignant neoplasm of fat cells that occurs in the retroperitoneal tissues and the thigh.
liposuction	Plastic surgery that removes subcutaneous fat using a suction tube.
-lipsis	omit, fail
liq.	liquid; fluid
-listhesis	slipping
lith/o	stone, calcification
lithiasis	Formation of stones in an internal organ, such as in the gallbladder, kidney, and lower urinary tract.
-lithiasis	presence of stones
-lithotomy	incision for stone removal
liver	A large lobed glandular organ in the abdomen with a wide range of function including detoxification, metabolism, synthesis and storage of various substances.
LLE	left lower extremity
LLL	left lower lobe
LLQ	left lower quadrant
lmp	last menstrual period
lob/o	lobe
lobe	A major division of an organ.
LOC	level/loss of consciousness
loc-	place
lochia	A vaginal discharge occurring during the first week or two after childbirth.
locomotion	Movement or the ability to move from one place or another.
locus	A place or site.
-log	speech, words, thought
log-	speech, words
logad/o	whites of the eyes
-logist	specialist
logo-	words, speech
-logy	study of
loin	The part of the side and back between the lowest rib and the pelvis.
longevity	An organism's life span.
longitudinal studies	Studies in which variables relating to an individual or group of individuals are assessed over an extended span of time.
loph/o	ridge, crested part
lord/o	curve, swayback
lordosis	Abnormal, concave curvature of the lower spine. Also called swayback.
lot.	lotion
loupe	A magnifying lens.
low density lipoprotein	Cholesterol that collects on blood vessel walls, increasing risk of heart problems.
lox/o	oblique, slanting
lozenge	A medicated candy.
LP	lumbar puncture
LR	lactated ringer (solution)
LRI	lower respiratory infection
LRT	lower respiratory tract
lubrication	The use of an agent such as grease to diminish friction between two surfaces.
luc/i	light
-lucent	light admitting
LUE	left upper extremity
LUL	left upper lobe
lumb/o	lower back
lumbago	Mild to severe low back pain.
lumbar	Referring to the lower back below the thoracic vertebrae and above the sacral vertebrae.
lumen	The channel within a tube or tubular organ.
lumin/o	lumen (channel within a tube)
luminescence	Emission of light from a body as a result of a chemical reaction.
lumpectomy	Surgical excision of a tumor from the breast without removing large amounts of surrounding tissue.
lungs	A pair of organs that aerate the blood. The right lung is divided into three lobs while the left lung has two lobes.
lupus	Any of a group of inflammatory autoimmune disorders can affect the skin, joints and internal organs.
LUQ	left upper quadrant
luteinizing hormone	A hormone released by the pituitary gland. It stimulates the secretion of sex hormones by the ovary and the testes and is involved in the maturation of spermatozoa and ova.
luteoma	An ovarian neoplasm composed of luteal cells derived from luteinized granulosa cells and theca cells.
LV	left ventricle
LVAD	left ventricular assist device
LVH	left ventricular hypertrophy
lyme disease	An subacute inflammatory disorder caused by a spirochete, Borrelia burgdorferi, which is transmitted chiefly by ticks. It is characterized by fatigue, concentration difficulties or joint pain.
lymph	The interstitial fluid that is in the lymphatic system.
lymph/o	lymph
lymphaden/o	lymph node
lymphadenitis	Inflammation of the lymph nodes.
lymphadenopathy	Inflammation of the lymph nodes causing enlargement.
lymphangi/o	lymph vessel
lymphangiectasis	A transient dilatation of the lymphatic vessels.
lymphangioma	A congenital malformation of the lymphatic system.
lymphangiosarcoma	A malignant neoplasm originating from the endothelial cells of lymphatic vessels.
lymphedema	Edema due to obstruction of lymph vessels or disorders of the lymph nodes. A common complication in the arms after mastectomy.
lymphocele	Cystic mass containing lymph.
lymphocytes	White blood cells that help determine the body's immune response to infectious microorganisms.
lymphocytosis	An abnormal increase in the number of lymphocytes in the blood.
lymphoma	A cancer of the lymphatic system.
lymphopenia	Decrease in the number of lymphocytes of the blood.
lymphuria	The presence of lymph in urine.
lysine	An essential amino acid.
-lysis	loosening, separating
lyso-	dissolution, loosen