<B>lactate dehydrogenase,</B><DL COMPACT><DD> an enzyme produced in animal tissue that oxidizes lactic acid and is released in increased amounts by cancerous cells. (Abbr:) LDH (no periods). </DL>
<A NAME="lactation">
<B>lactation, </B>noun.<DL COMPACT><DD><B> 1. </B>the secretion or formation of milk. <BR> <I>Ex. lactation records of cows.</I> <DD><B> 2. </B>the time during which a mother gives milk. <DD><B> 3. </B>the act of suckling a baby. </DL>
<A NAME="lactational">
<B>lactational, </B>adjective.<DL COMPACT><DD> of or having to do with lactation. <BR> <I>Ex. a lactational physiologist.</I> adv. <B>lactationally.</B> </DL>
<A NAME="lacteal">
<B>lacteal, </B>adjective, noun.<DL COMPACT><DD><I>adj. </I> <B>1. </B>of milk; like milk; milky. <BR> <I>Ex. a lacteal secretion.</I> <DD><B> 2. </B>carrying chyle, a milky liquid formed from digested food. <BR> <I>Ex. lacteal vessels.</I> <DD><I>noun </I> any one of the tiny lymphatic vessels that carry chyle from the small intestine to be absorbed by the blood. adv. <B>lacteally.</B> </DL>
<A NAME="lacteous">
<B>lacteous, </B>adjective. =milky.</DL>
<A NAME="lactescence">
<B>lactescence, </B>noun.<DL COMPACT><DD><B> 1. </B>a milky appearance; milkiness. <DD><B> 2. </B>an abundant flow of sap from a plant when wounded. The sap is commonly white, but sometimes red or yellow. </DL>
<A NAME="lactescent">
<B>lactescent, </B>adjective.<DL COMPACT><DD><B> 1. </B>becoming milky; having a milky appearance. <DD><B> 2. </B>producing or secreting milk. <DD><B> 3. </B>(of plants and insects) producing a milky fluid. </DL>
<A NAME="lactic">
<B>lactic, </B>adjective.<DL COMPACT><DD> of milk; from milk, especially sour milk. </DL>
<A NAME="lacticacid">
<B>lactic acid,</B><DL COMPACT><DD> a colorless, odorless, syrupy acid, formed by the action of lactobacilli in sour milk, the fermentation of vegetable juices, etc., and produced by muscle tissue during exercise. <BR> <I>Ex. Lactic acid [is] used normally in the manufacture of such essentials as leather, textiles, foods, and liquors (Science News Letter).</I> </DL>
<B>lactide, </B>noun.<DL COMPACT><DD> (Chemistry.) <DD><B> 1. </B>a compound formed by heating lactic acid, and regarded as an anhydride of that acid. <DD><B> 2. </B>any of a class of similar compounds. </DL>
<A NAME="lactiferous">
<B>lactiferous, </B>adjective.<DL COMPACT><DD><B> 1. </B>(of animals or their organs) secreting or conveying milk or a milky fluid. <DD><B> 2. </B>(of plants) yielding a milky juice. noun <B>lactiferousness.</B> </DL>
<B>lacto-,</B><DL COMPACT><DD> (combining form.) <DD><B> 1. </B>milk, as in <I>lactometer.</I> <DD><B> 2. </B>lactic acid, as in <I>lactobacillus.</I> Also, <B>lact-</B> before vowels. </DL>
<A NAME="lactobacillus">
<B>lactobacillus, </B>noun, pl. <B>-cilli.</B><DL COMPACT><DD> any one of a genus of aerobic bacteria that produces lactic acid with the fermentation of sugar. <BR> <I>Ex. It is not the acid-forming lactobacilli that cause tooth decay but another kind that attack the keratin of the teeth (Science News Letter).</I> </DL>
<A NAME="lactoduct">
<B>lactoduct, </B>noun.<DL COMPACT><DD> a plastic pipeline conveying milk from high mountain pastures to villages, especially in Switzerland. </DL>
<B>lactogen, </B>noun.<DL COMPACT><DD> a hormone that stimulates the secretion of milk. </DL>
<A NAME="lactogenesis">
<B>lactogenesis, </B>noun.<DL COMPACT><DD> the power of initiating milk secretion. </DL>
<A NAME="lactogenic">
<B>lactogenic, </B>adjective.<DL COMPACT><DD> stimulating the secretion and flow of milk. <BR> <I>Ex. lactogenic hormones.</I> </DL>
<A NAME="lactoglobulin">
<B>lactoglobulin, </B>noun.<DL COMPACT><DD> the globulin found in milk. </DL>
<A NAME="lactometer">
<B>lactometer, </B>noun.<DL COMPACT><DD> an instrument for testing the purity or richness of milk. </DL>
<A NAME="lactone">
<B>lactone, </B>noun.<DL COMPACT><DD> (Chemistry.) any of a group of cyclic anhydrides produced by the loss of a molecule of water from the hydroxyl (-OH) and carboxyl (-COOH) radicals of hydroxy acids. </DL>
<A NAME="lactonic">
<B>lactonic, </B>adjective.<DL COMPACT><DD> of or having to do with lactone. </DL>
<A NAME="lactophosphate">
<B>lactophosphate, </B>noun.<DL COMPACT><DD> a lactate and a phosphate in combination. </DL>
<A NAME="lactoprene">
<B>lactoprene, </B>noun.<DL COMPACT><DD> a synthetic rubber with high resistance to oils and heat, made from acrylate and acrylonitrile. </DL>
<A NAME="lactoprotein">
<B>lactoprotein, </B>noun.<DL COMPACT><DD> any protein found in milk. </DL>
<A NAME="lactoscope">
<B>lactoscope, </B>noun.<DL COMPACT><DD> an instrument for testing the purity or richness of milk by its resistance to the passage of light. </DL>
<A NAME="lactose">
<B>lactose, </B>noun.<DL COMPACT><DD> a crystalline sugar, present in milk; milk sugar. It is usually obtained by evaporating whey and converting it into hard, white crystals. Lactose is an isomer of common table sugar. </DL>
<A NAME="lactovegetarian">
<B>lactovegetarian, </B>adjective.<DL COMPACT><DD> consisting of a diet of milk and vegetables. </DL>
<A NAME="lacuna">
<B>lacuna, </B>noun, pl. <B>-nae,</B> <B>-nas.</B><DL COMPACT><DD><B> 1a. </B>an empty space; gap. <BR> <I>Ex. There was a lacuna in the old letter where the ink had faded.</I> <DD><B> b. </B>(Figurative:) <BR> <I>Ex. [He] has sought to fill, with this elegant collection of essays, a serious and regrettable lacuna in Italian studies (Saturday Review). Every teacher knows that the week before and after vacation is largely lost to study ... This means almost a month's lacuna (New York Times).</I> (SYN) hiatus. <DD><B> 2. </B>a tiny cavity or depression in bones or tissues. <DD><B> 3. </B>space in or among the cells of an animal or plant. </DL>
<A NAME="lacunal">
<B>lacunal, </B>adjective.<DL COMPACT><DD><B> 1. </B>of or having to do with a lacuna. <DD><B> 2. </B>having lacunas. </DL>
<A NAME="lacunar">
<B>lacunar, </B>noun, pl. <B>lacunars,</B> <B>lacunaria,</B> adjective.<DL COMPACT><DD><I>noun </I> <B>1. </B>(Architecture.) a ceiling formed of sunken compartments. <DD><B> 2. </B>one of the compartments; a sunken panel. <DD><I>adj. </I> of a lacuna or consisting of lacunae; lacunal. </DL>
<A NAME="lacunary">
<B>lacunary, </B>adjective. =lacunal.</DL>
<A NAME="lacunate">
<B>lacunate, </B>adjective. =lacunal.</DL>
<A NAME="lacune">
<B>lacune, </B>noun. =lacuna.</DL>
<A NAME="lacunose">
<B>lacunose, </B>adjective.<DL COMPACT><DD> having lacunas; pitted; furrowed. </DL>
<B>lacunulose, </B>adjective.<DL COMPACT><DD> minutely pitted or furrowed. </DL>
<A NAME="lacustrian">
<B>lacustrian, </B>adjective, noun.<DL COMPACT><DD><I>adj. </I> <B>=lacustrine.</B> <DD><I>noun </I> a lake dweller. </DL>
<A NAME="lacustrine">
<B>lacustrine, </B>adjective.<DL COMPACT><DD><B> 1. </B>of lakes. <BR> <I>Ex. lacustrine mire.</I> <DD><B> 2. </B>living or growing in lakes. <BR> <I>Ex. lacustrine water fleas.</I> <DD><B> 3. </B>(Geology.) of or having to do with strata that originated by deposition at the bottom of a lake. <BR> <I>Ex. Lacustrine plains are one of the flattest landforms extant.</I> </DL>
<A NAME="lacy">
<B>lacy, </B>adjective, <B>lacier,</B> <B>laciest.</B><DL COMPACT><DD><B> 1. </B>of lace. <BR> <I>Ex. The little girl wore a lacy frock.</I> <DD><B> 2. </B>like lace; having an open delicate pattern. <BR> <I>Ex. the lacy leaves of a fern.</I> <DD> Also, <B>lacey.</B> </DL>
<A NAME="lacyglass">
<B>lacy glass,</B><DL COMPACT><DD> glass pressed with designs of a lacy appearance, made especially in the United States in the early 1800's. </DL>
<A NAME="lad">
<B>lad, </B>noun.<DL COMPACT><DD><B> 1. </B>a boy; youth. <BR> <I>Ex. The little lad was playing on the swing. ... he was then a gallant lad on the ready for new ideas (Lillian Smith).</I> (SYN) stripling, youngster. <DD><B> 2. </B>(Informal.) a man. <BR> <I>Ex. How now, old lad? (Shakespeare).</I> (SYN) fellow, chap. </DL>
<A NAME="ladak">
<B>Ladak, </B>noun.<DL COMPACT><DD> a variety of winter-hardy alfalfa that resists drought, but not wilt. </DL>
<A NAME="ladang">
<B>ladang, </B>noun.<DL COMPACT><DD> a system of cultivation practiced by farmers in Indonesia and Malaysia, in which they clear a part of the jungle and farm it until the soil is exhausted, after which they move on to another part and repeat the process. </DL>
<A NAME="ladanum">
<B>ladanum, </B>noun. =labdanum.</DL>
<A NAME="ladder">
<B>ladder, </B>noun, verb.<DL COMPACT><DD><I>noun </I> <B>1. </B>a set of rungs or steps fastened into two long sidepieces of wood, metal, or rope, for use in climbing. <BR> <I>Ex. The boys climbed the rope ladder to get into their tree house.</I> <DD><B> 2. </B>(Figurative.) a means of climbing higher. <BR> <I>Ex. Hard work is often a ladder to success.</I> <DD><B> 3. </B>(Figurative:) <BR> <I>Ex. This company has an elaborate promotion ladder. The mathematician has reached the highest rung on the ladder of human thought (Havelock Ellis).</I> <DD><B> 4. </B>a series of steps to enable fish to ascend a fall or dam by a succession of leaps; fish ladder. <DD><B> 5. </B>(British.) a run in a stocking or other knitted garment, especially a silk or nylon stocking. <DD><I>v.i., v.t. </I> (British.) to develop runs in (a knitted garment, such as a stocking) as the result of the breaking of a thread. adj. <B>ladderless.</B> adj. <B>ladderlike.</B> </DL>
<A NAME="ladderbackchair">
<B>ladder-back chair,</B><DL COMPACT><DD> a chair having a back formed of horizontal pieces of wood between two upright pieces, such as a ladder has. </DL>
