<B>thymus, </B>noun, adjective.<DL COMPACT><DD><I>noun </I> <B>=thymus gland.</B> <DD><I>adj. </I> of or having to do with the thymus gland. </DL>
<A NAME="thymusgland">
<B>thymus gland,</B><DL COMPACT><DD> a small, ductless gland near the base of the neck, found in young vertebrates. It disappears or becomes rudimentary in the adult. The thymus gland aids in the development of lymphocytes necessary to protect the young from disease. The thymus of lambs and calves is used for food and is called sweetbread. </DL>
<A NAME="thymusnucleicacid">
<B>thymus nucleic acid,</B><DL COMPACT><DD> deoxyribonucleic acid, originally extracted from the thymus gland. </DL>
<A NAME="thymy">
<B>thymy, </B>adjective.<DL COMPACT><DD> having to do with or like thyme; full of thyme. <BR> <I>Ex. thymy hills.</I> </DL>
<A NAME="thyratron">
<B>thyratron, </B>noun.<DL COMPACT><DD> a gas-filled, three- or four-element vacuum tube containing a hot cathode, in which the grid initiates, but does not limit, the current. It is used mainly as an electronic switch. </DL>
<A NAME="thyristor">
<B>thyristor, </B>noun.<DL COMPACT><DD> a transistor or semiconductor that forms an open circuit until signaled to switch to the conducting state by a controlling electrode. <BR> <I>Ex. If thyristors are used to control the motor of an electric car, the vehicle moves smoothly but with poor efficiency at low speeds (New Scientist).</I> </DL>
<A NAME="thyroactive">
<B>thyroactive, </B>adjective.<DL COMPACT><DD> stimulating the activity of thyroxine and other secretions of the thyroid gland. </DL>
<A NAME="thyroarytenoid">
<B>thyroarytenoid, </B>adjective.<DL COMPACT><DD> having to do with or connecting the thyroid and arytenoid cartilages of the larynx. </DL>
<A NAME="thyrocalcitonin">
<B>thyrocalcitonin, </B>noun. =calcitonin.</DL>
<A NAME="thyroglobulin">
<B>thyroglobulin, </B>noun.<DL COMPACT><DD> a protein of the thyroid gland that contains iodine, found in the colloid substance of the gland. </DL>
<A NAME="thyroid">
<B>thyroid, </B>noun, adjective.<DL COMPACT><DD><I>noun </I> <B>1. </B><B>=thyroid gland.</B> <DD><B> 2. </B>a medicine made from the thyroid glands of certain domestic animals, used in the treatment of goiter, obesity, and other disorders caused by a deficiency in the thyroid gland. <DD><B> 3. </B><B>=thyroid cartilage.</B> <DD><B> 4. </B>a part of the body, such as a vein, near the thyroid gland. <DD><I>adj. </I> of or having to do with the thyroid gland or the thyroid cartilage. <BR> <I>Ex. thyroid extract.</I> </DL>
<A NAME="thyroidal">
<B>thyroidal, </B>adjective. =thyroid.</DL>
<A NAME="thyroidbody">
<B>thyroid body,</B> =thyroid gland.</DL>
<A NAME="thyroidcartilage">
<B>thyroid cartilage,</B><DL COMPACT><DD> the principal cartilage of the larynx, which forms the lump called the Adam's apple in human beings. </DL>
<A NAME="thyroidectomize">
<B>thyroidectomize, </B>transitive verb, <B>-mized,</B> <B>-mizing.</B><DL COMPACT><DD> to subject to thyroidectomy. </DL>
<A NAME="thyroidectomy">
<B>thyroidectomy, </B>noun, pl. <B>-mies.</B><DL COMPACT><DD> the surgical removal of all or part of the thyroid gland. </DL>
<A NAME="thyroidgland">
<B>thyroid gland,</B><DL COMPACT><DD> an important ductless gland in the neck of vertebrates, near the larynx and upper windpipe, that affects growth and metabolism. An enlargement of the thyroid gland is called a goiter. Thyroxine is secreted by the thyroid gland. </DL>
<A NAME="thyroiditis">
<B>thyroiditis, </B>noun.<DL COMPACT><DD> inflammation of the thyroid gland. </DL>
<B>thyrotropin, </B>noun.<DL COMPACT><DD> a hormone produced by the pituitary gland, that regulates the activity of the thyroid gland. </DL>
<A NAME="thyroxin">
<B>thyroxin, </B>noun. =thyroxine.</DL>
<A NAME="thyroxine">
<B>thyroxine, </B>noun.<DL COMPACT><DD> a white, crystalline amino acid, the principal secretion of the thyroid gland, which stimulates metabolism and, in children, affects growth. A synthetic form is used to treat goiter and other thyroid disorders. </DL>
<B>thyrsus, </B>noun, pl. <B>-si.</B><DL COMPACT><DD><B> 1. </B>(Greek Mythology.) a staff or spear tipped with an ornament like a pine cone and sometimes wrapped around with ivy and vine branches. It was carried by Dionysus (Bacchus) and his followers. <DD><B> 2. </B>(Botany.) a form of mixed inflorescence, a contracted panicle, in which the main ramification is indeterminate and the secondary or ultimate is determinate, as in the lilac and horse chestnut. </DL>
<A NAME="thysanuran">
<B>thysanuran, </B>noun, adjective.<DL COMPACT><DD><I>noun </I> any one of an order of wingless insects having long antennae, a scaly, flattened body that is silvery or gray in color, and two or three slender caudal appendages. Silverfishes and bristletails are thysanurans. <DD><I>adj. </I> of or belonging to this order. </DL>
<B>ti</B> (1), noun.<DL COMPACT><DD> (Music.) the seventh tone of the diatonic scale; si. </DL>
<A NAME="ti">
<B>ti</B> (2), noun, pl. <B>tis.</B><DL COMPACT><DD> any one of various Polynesian and Asian palmlike shade trees and shrubs of the agave family; ti palm. The elongated leaves of one species are often used for food wrappers or hula skirts. </DL>
<A NAME="ti">
<B>Ti</B> (no period),<DL COMPACT><DD> titanium (chemical element). </DL>
<A NAME="tianshansheep">
Tian-shan sheep, =Marco Polo sheep.</DL>
<A NAME="tiara">
<B>tiara, </B>noun.<DL COMPACT><DD><B> 1. </B>a band of gold, jewels, or flowers worn by women around the head as an ornament. (SYN) coronet. <DD><B> 2a. </B>the triple crown worn by the pope as a symbol of his position. <DD><B> b. </B>(Figurative.) the position or authority of the pope. <DD><B> 3. </B>an ancient Persian headdress worn by men. </DL>
<A NAME="tiaraed">
<B>tiaraed, </B>adjective.<DL COMPACT><DD> adorned with a tiara or tiaras. </DL>
<A NAME="tibbu">
<B>Tibbu, </B>noun, pl. <B>-bu</B> or <B>-bus.</B><DL COMPACT><DD> a member of a Negro people of mixed ancestry living in the southeastern part of the Sahara. </DL>
<A NAME="tibet">
<B>tibet, </B>noun, or <B>tibet cloth,</B><DL COMPACT><DD> a soft, smooth, twilled woolen cloth. </DL>
<A NAME="tibetan">
<B>Tibetan, </B>adjective, noun.<DL COMPACT><DD><I>adj. </I> of or having to do with Tibet, a region in southwestern China, its people, or their language. <DD><I>noun </I> <B>1. </B>a person born or living in Tibet. <DD><B> 2. </B>the Sino-Tibetan language of Tibet. Tibetan is related to Burmese and Thai. Also, <B>Thibetan.</B> </DL>
<A NAME="tibetanterrier">
<B>Tibetan terrier,</B><DL COMPACT><DD> any one of a breed of dog that originated in Tibet. Tibetan terriers resemble Old English sheepdogs but are smaller, standing from 14 to 16 inches high, and have a fluffy tail that curls over the dog's back. </DL>
<A NAME="tibetoburman">
<B>Tibeto-Burman, </B>noun.<DL COMPACT><DD> a subdivision of the Sino-Tibetan language family, including Tibetan and Burmese. </DL>
<A NAME="tibia">
<B>tibia, </B>noun, pl. <B>-iae,</B> <B>-ias.</B><DL COMPACT><DD><B> 1. </B>the inner and thicker of the two bones of the leg, from the knee to the ankle; shinbone. <DD><B> 2. </B>a corresponding bone in amphibians, birds, reptiles, and mammals. <DD><B> 3. </B>the fourth section (from the body) of the leg of an insect. <DD><B> 4. </B>an ancient Roman flute. <DD><B> 5. </B>one of several organ stops, mostly of the flute family. </DL>
<A NAME="tibial">
<B>tibial, </B>adjective.<DL COMPACT><DD> of or having to do with the tibia. </DL>
<A NAME="tibiofibular">
<B>tibiofibular, </B>adjective.<DL COMPACT><DD> of or having to do with both the tibia and the fibula. <BR> <I>Ex. the posterior tibiofibular ligament.</I> </DL>
<A NAME="tic">
<B>tic, </B>noun.<DL COMPACT><DD><B> 1. </B>a habitual, involuntary twitching of the muscles, especially those of the face. <DD><B> 2. </B><B>=tic douloureux.</B> </DL>
<A NAME="tical">
<B>tical, </B>noun, pl. <B>-cals</B> or <B>-cal.</B><DL COMPACT><DD><B> 1. </B>a former Siamese (Thai) monetary unit and silver coin, worth 100 satang, now replaced by the baht. <DD><B> 2. </B>a former Siamese (Thai) unit of weight, equal to 231.5 grains, or about half an ounce troy. </DL>
<A NAME="ticdouloureux">
<B>tic douloureux,</B><DL COMPACT><DD> a severe facial neuralgia, especially of the trigeminal nerve, accompanied by twitching. </DL>
