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(trī-jĕm′ĭ-nē) Occurring in threes, esp. three pulse beats in rapid succession.


(trī-jĕn′ĭk) [Gr. treis, three, + gennan, to produce] In genetics, a condition in which three alleles are present at any particular locus on the chromosome.


(trig′ĕr) 1. Stimulus. 2. To initiate or start with suddenness. 3. A chemical that initiates a function or action.


The initiation of a mechanically generated breath after the detection of a change in airway pressure, after a change in air flow, or after an alteration in the flow wave form.

trigger point dry needling

ABBR: TrPDN. Intramuscular stimulation.


(trī-glĭs′ĕr-īd) Any combinations of glycerol with three of five different fatty acids. These substances, triacylglycerols, are also called neutral fats. In the blood, triglycerides are combined with proteins to form lipoproteins. The liver synthesizes lipoproteins to transport fats to other tissues, where they are a source of energy. Fat in adipose tissue is stored energy. SYN: triacylglycerol. SEE: hyperlipoproteinemia.

medium-chain t. Triglycerides with 8 to 10 carbon atoms. They are absorbed differently from long chain fatty acids, i.e., via the portal vein through the liver rather than as chylomicrons transported via the lymphatics, and therefore, have been used to treat malabsorption.


(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.

t. of bladder Trigone.

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.



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