| undecyl | <chemistry> The radical regarded as characteristic of undecylic acid. Origin: Undecane + -yl. Source: Websters Dictionary (01 Mar 1998) |
|---|---|
| undecylenate | A salt of undecylenic acid. (05 Mar 2000) |
| undecylenic | <chemistry> Pertaining to, or designating, an acid C11H20O2, homologous with acrylic acid, and obtained as a white crystalline substance by the distillation of castor oil. Source: Websters Dictionary (01 Mar 1998) |
| undecylenic acid | CH2CH(CH2)8COOH;an acid present in small amounts in sweat; used with its zinc salt in ointments, or as a powder in the treatment of fungus diseases of the skin, psoriasis, and certain other cutaneous affections. Synonym: undecenoic acid. (05 Mar 2000) |
| undecylic | <chemistry> Related to, derived from, or containing, undecyl; specifically, designating that member of the fatty acids which corresponds to undecane, and is obtained as a white crystalline substance, C11H22O2. Source: Websters Dictionary (01 Mar 1998) |
| under | In a lower, subject, or subordinate condition; in subjection; used chiefly in a few idiomatic phrases; as, to bring under, to reduce to subjection; to subdue; to keep under, to keep in subjection; to control; to go under, to be unsuccessful; to fail. "I keep under my body, and bring it into subjection." (1 Cor. Ix. 27) "The minstrel fell, but the foeman's chain Could not bring his proud soul under." (Moore) Under is often used in composition with a verb to indicate lowness or inferiority in position or degree, in the act named by the verb; as, to underline; to undermine; to underprop. 1. Below or lower, in place or position, with the idea of being covered; lower than; beneath; opposed to over; as, he stood under a tree; the carriage is under cover; a cellar extends under the whole house. "Fruit put in bottles, and the bottles let down into wells under water, will keep long." (Bacon) "Be gathered now, ye waters under heaven, Into one place." (Milton) 2. Hence, in many figurative uses which may be classified as follows. Denoting relation to some thing or person that is superior, weighs upon, oppresses, bows down, governs, directs, influences powerfully, or the like, in a relation of subjection, subordination, obligation, liability, or the like; as, to travel under a heavy load; to live under extreme oppression; to have fortitude under the evils of life; to have patience under pain, or under misfortunes; to behave like a Christian under reproaches and injuries; under the pains and penalties of the law; the condition under which one enters upon an office; under the necessity of obeying the laws; under vows of chastity. "Both Jews and Gentiles . . . Are all under sin." (Rom. Iii. 9) "That led the embattled seraphim to war Under thy conduct." (Milton) "Who have their provand Only for bearing burdens, and sore blows For sinking under them." (Shak) Denoting relation to something that exceeds in rank or degree, in number, size, weight, age, or the like; in a relation of the less to the greater, of inferiority, or of falling short. "Three sons he dying left under age." (Spenser) "Medicines take effect sometimes under, and sometimes above, the natural proportion of their virtue." (Hooker) "There are several hundred parishes in England under twenty pounds a year." (Swift) "It was too great an honor for any man under a duke." (Addison) Hence, it sometimes means at, with, or for, less than; as, he would not sell the horse under sixty dollars. "Several young men could never leave the pulpit under half a dozen conceits." (Swift) Denoting relation to something that comprehends or includes, that represents or designates, that furnishes a cover, pretext, pretense, or the like; as, he betrayed him under the guise of friendship; Morpheus is represented under the figure of a boy asleep. "A crew who, under names of old renown . . . Abused Fanatic Egypt." (Milton) "Mr. Duke may be mentioned under the double capacity of a poet and a divine." (Felton) "Under this head may come in the several contests and wars betwixt popes and the secular princes." (C. Leslie) Less specifically, denoting the relation of being subject, of undergoing regard, treatment, or the like; as, a bill under discussion. "Abject and lost, lay these, covering the flood, Under amazement of their hideous change." (Milton) Under arms. <medicine> In a condition to make progress; having started. Origin: AS. Under, prep. & adv.; akin to OFries. Under, OS. Undar, D. Onder, G. Unter, OHG. Untar, Icel. Undir, Sw. & Dan. Under, Goth. Undar, L. Infra below, inferior lower, Skr. Adhas below. Cf. Inferior. Lower in position, intensity, rank, or degree; subject; subordinate; generally in composition with a noun, and written with or without the hyphen; as, an undercurrent; undertone; underdose; under-garment; underofficer; undersheriff. <zoology> Under covert, one of the feathers situated beneath the bases of the quills in the wings and tail of a bird. Source: Websters Dictionary (01 Mar 1998) |
| underachievement | Performance, usually in school work, poorer than that predicted from aptitude and/or intelligence testing. (12 Dec 1998) |
| underachiever | One who manifests underachievement. (05 Mar 2000) |
| underbite | A nontechnical term applied to mandibular underdevelopment or to excessive maxillary development. (05 Mar 2000) |
| underbrush | Shrubs, small trees, and the like, in a wood or forest, growing beneath large trees; undergrowth. Source: Websters Dictionary (01 Mar 1998) |
| underclay | <geology> A stratum of clay lying beneath a coal bed, often containing the roots of coal plants, especially the Stigmaria. Source: Websters Dictionary (01 Mar 1998) |
| underclothes | Clothes worn under others, especially those worn next the skin for warmth. Source: Websters Dictionary (01 Mar 1998) |
| undercut | 1. That portion of a tooth that lies between the survey line (height of contour) and the gingivae. 2. The contour of a cross-section of a residual ridge or dental arch which would prevent the insertion of a denture. 3. The contour of a flasking stone which interlocks in such a way as to prevent the separation of the parts. (05 Mar 2000) |
| undercut gauge | A device, used with a surveyor, to precisely locate areas for the placement of the retentive components of clasps when designing removable partial dentures. (05 Mar 2000) |
| underdrive pacing | Electrical stimulation of the heart at a rate lower than that of an existing tachycardia; designed to capture the heart between beats, i.e., to interrupt a reentry pathway in order to terminate the tachycardia. (05 Mar 2000) |