Dictionary

Body systems

Anatomy and the conditions of each body system, from the heart and lungs to the skin.

tissueA group of similar cells that work together to do a job in the body.

TNMTumor, Node, Metastasis: a system for describing how far a cancer has grown and spread.

tonic neck reflexA newborn reflex: when the baby's head turns toward one side, the arm and leg on that side stretch out while the opposite limbs bend.

tonsilOne of the masses of lymph tissue at the back of the throat that help fight germs entering the mouth and nose.

tonsillitisInflammation of the tonsils, the two lumps of lymph tissue at the back of the throat.

torsades de pointesA fast ventricular heart rhythm in which the QRS complexes on the ECG seem to twist around the baseline.

total knee replacementSurgery that replaces the worn surfaces of the knee joint with metal and plastic parts.

total parenteral nutritionComplete nutrition given as a liquid straight into a vein instead of through the digestive tract.

total thyroidectomySurgery to remove the whole thyroid gland.

toxic shock syndromeA rare, life-threatening illness caused by toxins from certain bacteria, mainly Staphylococcus aureus or group A streptococcus.

toxoplasmosisAn infection with Toxoplasma gondii, a parasite carried by cats and found in undercooked meat and soil.

tracheaThe windpipe: the tube that carries air from the throat to the lungs.

tracheostomyA surgical opening through the front of the neck into the windpipe, usually holding a tube that the person breathes through.

tractionA steady pulling force applied to a body part with weights, ropes and pulleys.

transfusion reactionA harmful response of the body to a blood transfusion.

transient ischemic attackA short-lived blockage of blood flow to part of the brain that clears on its own and leaves no lasting brain damage.

transposition of the great arteriesA heart defect present at birth in which the aorta and the pulmonary artery are attached to the wrong ventricles.

transurethral resection of the prostateSurgery that removes part of the prostate gland with an instrument passed up through the urethra.

transverseLying across something, at a right angle to its length.

traumaA physical injury to the body, or a deeply distressing event and the emotional harm it leaves.

traumaticCaused by an injury, or relating to a deeply distressing event.

traumatic brain injuryDamage to the brain caused by an outside force, such as a blow or jolt to the head or an object entering the skull.

tremorShaking of a part of the body, such as the hands, in small rhythmic movements that the person cannot control.

trichomoniasisA common sexually transmitted infection caused by a one-celled parasite, Trichomonas vaginalis.

tricuspid valveThe heart valve between the right atrium and the right ventricle.

trimesterOne of the three periods, each about three months long, that a pregnancy is divided into.

trisomyHaving three copies of a chromosome instead of the usual two.

tRNATransfer RNA: small RNA molecules that carry amino acids to the ribosome while a cell builds a protein.

tuberculosisAn infection caused by the bacterium Mycobacterium tuberculosis, which most often attacks the lungs.

tubuleA very small tube in the body, most often one of the tiny tubes in the kidney that turn filtered fluid into urine.

tumorAn abnormal mass of tissue formed when cells grow and divide more than they should.

Turner syndromeA genetic condition in females in which all or part of one X chromosome is missing.

twitchingSmall, quick movements of a muscle or part of a muscle that happen without control.

tympanic membraneThe thin, cone-shaped sheet of tissue between the outer ear canal and the middle ear; the eardrum.

type 1 diabetesA form of diabetes in which the pancreas makes little or no insulin because the immune system has destroyed the cells that make it.

type 2 diabetesA form of diabetes in which the body does not respond well to insulin and does not make enough of it to keep blood glucose normal.

U waveA small, rounded wave that sometimes follows the T wave on an ECG.

UCAn abbreviation with two common meanings: ulcerative colitis or uterine contractions; the setting shows which.

ulcerAn open sore where the skin or the lining of an organ has broken down.

ulcerative colitisA long-term inflammatory bowel disease that affects the inner lining of the colon and rectum.

umbilical cordThe cord that connects the unborn baby to the placenta, carrying oxygen and nutrients to the baby and wastes away.

umbilical cord prolapseA condition in which the umbilical cord slips through the cervix ahead of or beside the fetus's presenting part.

umbilicusThe navel: the scar in the middle of the abdomen where the umbilical cord was attached before birth.

unilateralOn or affecting only one side of the body.

upper respiratory infectionAn infection of the nose, sinuses, throat or voice box, such as the common cold.

ureaA waste product the liver makes when it breaks down protein, which the kidneys remove in urine.

ureterOne of the two tubes that carry urine from the kidneys down to the bladder.

urethraThe tube that carries urine from the bladder out of the body.

urgencyA sudden, strong need to pass urine that is hard to put off.

urinaryHaving to do with urine or with the organs that make, store and pass urine.