(trī′gōn″) [L. trigonum, fr Gr. trigōnos, trigōnon, triangular, triangle] A triangular space, esp. one at the base of the bladder, between the two openings of the ureters and the urethra. trigonal (trig′ŏ-năl), adj. SYN: t. of bladder.
carotid t. The triangular area in the neck bounded by the posterior belly of the digastric muscle, the sternocleidomastoid muscle, and the midline of the neck.
collateral t. The angle between the diverging inferior and posterior horns of the lateral ventricle.
habenular t. A depressed triangular area located on the lateral aspect of the posterior portion of the third ventricle. It contains a medial and lateral habenular nucleus.
olfactory t. A small triangular eminence at the root of the olfactory peduncle and anterior to the anterior perforated space of the base of the brain.
retromolar t. The space between the most posterior wisdom tooth and the back wall of the mouth It is sometimes invaded by tumors of the head and neck, esp. squamous cell cancers.
(trī″gōn-ĕk′tō-mē) [″ + ektome, excision] Excision of the base of the bladder.
Trigonella foenum graecum
(trig″ŏ-nel′ă fē′nŭm grēk′ŭm) SEE: fenugreek.
(trī-gō′nĭd) The first three cusps of a lower molar tooth.
(trĭg″ō-nī′tĭs) [″ + itis, inflammation] Inflammation of the mucous membrane of the trigone of the bladder.
(trĭg″ō-nō-sĕf′ă-lŭs) A fetus exhibiting trigonocephaly.
(trī-gō″nō-sĕf′ă-lē) The condition of the head of the fetus being shaped like a triangle.
(trī-hī′brĭd) [Gr. treis, three, + L. hybrida, mongrel] In genetics, the offspring of a cross between two individuals differing in three unit characters.
(trī″ī-ō″dō-thī′rŏ-nēn″) ABBR: T3. The active form of thyroid hormone. A small amount is secreted directly from the thyroid, but most of it is converted from thyroxine via deiodinase enzymes. T3 acts directly on receptors in the nucleus to modify the protein output of the cell. Chemically it is 3,5,3 -triiodothyronine (liothyronine). SEE: tetraiodothyronine; thyroid gland; thyroid function test; thyroxine.
(trī-lăm′ĭ-năr) Composed of three layers.
(trī-lin′ē-ăj) [tri- + lineage] Pert. to or affecting all three types of blood cells (red cells, white cells, and platelets).
(trĭl) [It. trillare, probably imitative] A tremulous sound, esp. in vocal music.