| reversed-three sign | On an oesophagram of a patient with coarctation of the aorta, the shape of the contrast-filled oesophagus caused by the aortic arch (upper convexity) and post-stenotic dilatation (lower convexity); the cusp of the backwards 3 is at the level of the coarctation itself. (05 Mar 2000) |
|---|---|
| three | One more than two; two and one. "I offer thee three things." "Three solemn aisles approach the shrine." (Keble) Three is often joined with other words, forming compounds signifying divided into, composed of, or containing, three parts, portions, organs, or the like; as, three-branched, three-capsuled, three-celled, three-cleft, three-edged, three-foot, three-footed, three-forked, three-grained, three-headed, three-legged, three-mouthed, three-nooked, three-petaled, three-pronged, three-ribbed, three-seeded, three-stringed, three-toed, and the like. Origin: OE. Thre, threo, thri, AS. Thri, masc, threo, fem. And neut.; akin to OFries. Thre, OS. Thria, threa, D. Drie, G. Drei, OHG. Dri, Icel. Thrir, Dan. & Sw. Tre, Goth. Threis, Lith. Trys, Ir, Gael. & W. Tri, Russ. Tri, L. Tres, Gr. Trei^s, Skr. Tri. 301. Cf. 3d Drilling, Tern, Third, Thirteen, Thirty, Tierce, Trey, Tri-, Triad, Trinity, Tripod. 1. The number greater by a unit than two; three units or objects. 2. A symbol representing three units, as 3 or III. Rule of three. <mathematics> See Rule. Source: Websters Dictionary (01 Mar 1998) |
| three-body collisions | <radiobiology> It is possible (but generally rare) to have three particles collide simultaneously, instead of just two. (09 Oct 1997) |
| three-chambered heart | Congenital abnormality in which there may be a single atrium with two ventricles or a single ventricle with two atria. Rudimentary parts of the atrial and ventricular septa may be present but are incompetent to prevent a virtual single chamber in either case. (05 Mar 2000) |
| three-cornered | 1. Having three corners, or angles; as, a three-cornered hat. 2. <botany> Having three prominent longitudinal angles; as, a three-cornered stem. Source: Websters Dictionary (01 Mar 1998) |
| three-cornered bone | A bone on the medial (ulnar) side of the proximal row of the carpus, articulating with the lunate, pisiform, and hamate. Synonym: os triquetrum, cubital bone, os pyramidale, os triangulare, pyramidal bone, pyramidale, three-cornered bone, triquetrum. (05 Mar 2000) |
| three-day fever | Influenza-like febrile viral disease caused by several members of the bunyaviridae family and transmitted mostly by the bloodsucking sandfly phlebotomus papatasii. (12 Dec 1998) |
| three-day measles | <disease, virology> An acute, usually benign, infectious disease caused by a togavirus and most often affecting children and nonimmune young adults, in which the virus enters the respiratory tract via droplet nuclei and spreads to the lymphatic system. It is characterised by a slight cold, sore throat and fever, followed by enlargement of the postauricular, suboccipital and cervical lymph nodes and the appearances of a fine pink rash that begins on the head and spreads to become generalised. Synonym: German measles, rubeola. Origin: L. Rubellus = reddish, ruber = red (17 Dec 1997) |
| three-dimensional diffraction pattern | <optics> The diffraction pattern (of a point source) that appears in the three-dimensional space in and near the focal plane. For an aberration-free, diffraction- limited system, the slice of the diffraction pattern in the focal plane is the Airy disk and its surrounding diffraction rings. Above and below focus, the pattern changes periodically along the axis of the light beam so that bright and dark Airy-disk-like patterns appear alternately. The axial period of repeat is spaced twice as far apart as the radial period of repeat in the Airy disk and its diffraction rings (05 Aug 1998) |
| three-dimensional record | A maxillomandibular record made at the occluding relation. (05 Mar 2000) |
| three-flowered | <botany> Bearing three flowers together, or only three flowers. Source: Websters Dictionary (01 Mar 1998) |
| three-glass test | The bladder is emptied by passing urine into a series of 3-ounce test tubes, and the contents of the first and the last are examined; the first tube contains the washings from the anterior urethra, the second, material from the bladder, and the last, material from the posterior urethra, prostate, and seminal vesicles. Synonym: Valentine's test. (05 Mar 2000) |
| three-leafed | <botany> Producing three leaves; as, three-leaved nightshade. Consisting of three distinct leaflets; having the leaflets arranged in threes. Three-leaved nightshade. See Trillium. Source: Websters Dictionary (01 Mar 1998) |
| three-leaved | <botany> Producing three leaves; as, three-leaved nightshade. Consisting of three distinct leaflets; having the leaflets arranged in threes. Three-leaved nightshade. See Trillium. Source: Websters Dictionary (01 Mar 1998) |
| three-lobed | Having three lobes. <botany> Three-lobed leaf, a leaf divided into three parts, the sinuses extending not more than half way to the middle, and either the parts of the sinuses being rounded. Source: Websters Dictionary (01 Mar 1998) |