<B>mesonephric, </B>adjective.<DL COMPACT><DD> of or having to do with the mesonephros. </DL>
<A NAME="mesonephricduct">
<B>mesonephric duct,</B><DL COMPACT><DD> the embryonic genital or reproductive tract of males in vertebrate animals; Wolffian duct. </DL>
<A NAME="mesonephros">
<B>mesonephros, </B>noun, pl. <B>-roi.</B><DL COMPACT><DD> the middle division of the primitive kidney of vertebrate embryos, the pronephros and the metanephros being the anterior and posterior divisions, respectively; Wolffian body. The mesonephros becomes part of the permanent kidney in fishes and amphibians. </DL>
<A NAME="mesonfactory">
<B>meson factory,</B><DL COMPACT><DD> a particle accelerator designed to produce intense beams of mesons with which to probe atomic nuclei. </DL>
<A NAME="mesopause">
<B>mesopause, </B>noun.<DL COMPACT><DD> the area of atmospheric demarcation between the mesosphere and the exosphere. <BR> <I>Ex. Near the mesopause there is a change in the nature of the air motion and tidal effects begin to dominate (New Scientist).</I> </DL>
<A NAME="mesophase">
<B>mesophase, </B>noun.<DL COMPACT><DD> a semicrystalline phase of some substances, such as liquid crystals. </DL>
<B>mesophilic, </B>adjective.<DL COMPACT><DD> requiring moderate temperatures for development. <BR> <I>Ex. They studied ... flagella from mesophilic bacteria that live under more temperate conditions (Science News Letter).</I> </DL>
<A NAME="mesophyll">
<B>mesophyll</B> or <B>mesophyl, </B>noun.<DL COMPACT><DD> the inner green tissue of a leaf, lying between the upper and lower layers of epidermis; parenchyma of a leaf. </DL>
<A NAME="mesophyte">
<B>mesophyte, </B>noun.<DL COMPACT><DD> a plant that grows under conditions of average moisture and dryness. Mesophytes are intermediate between hydrophytes and xerophytes. </DL>
<A NAME="mesophytic">
<B>mesophytic, </B>adjective.<DL COMPACT><DD> of or having to do with a mesophyte. </DL>
<A NAME="mesopotamian">
<B>Mesopotamian, </B>adjective, noun.<DL COMPACT><DD><I>adj. </I> of or having to do with Mesopotamia (an ancient country in southwestern Asia between the Tigris and Euphrates rivers). <DD><I>noun </I> a native or inhabitant of Mesopotamia. </DL>
<A NAME="mesoscale">
<B>mesoscale, </B>adjective.<DL COMPACT><DD> of or having to do with atmospheric phenomena intermediate between microscale and macroscale. <BR> <I>Ex. Mesoscale meteorology [is] the meteorology of areas 10 to 20 miles in diameter, or about the size of many urban areas (Science News).</I> </DL>
<A NAME="mesoscaph">
<B>mesoscaph</B> or <B>mesoscaphe, </B>noun.<DL COMPACT><DD> an apparatus similar to the bathyscaph, used to explore the middle depths of the ocean. <BR> <I>Ex. The existence of these many portholes, with the possibility of looking in virtually every direction, is a principal characteristic of the mesoscaph and distinguishes her from naval or combatant submarines (Jacques Piccard).</I> </DL>
<A NAME="mesoseismal">
<B>mesoseismal, </B>adjective.<DL COMPACT><DD> having to do with the center of intensity of an earthquake. </DL>
<A NAME="mesosome">
<B>mesosome, </B>noun.<DL COMPACT><DD> a structure on cell membranes which has to do with the formation of the cross wall when a cell divides. <BR> <I>Ex. The mesosome [is] a structure which can be observed in electron micrographs of bacteria ... It is the point at which DNA is attached to the cell membrane (New Scientist).</I> </DL>
<A NAME="mesosphere">
<B>mesosphere, </B>noun.<DL COMPACT><DD><B> 1. </B>the region of the earth's atmosphere between the stratosphere and the ionosphere, which extends from about 30 to 50 miles above the earth's surface. Most of the ozone in the atmosphere is created in the mesosphere, and there is almost no variation in the temperature. <DD><B> 2. </B>the region of the earth's atmosphere between the ionosphere and the exosphere. </DL>
<A NAME="mesospheric">
<B>mesospheric, </B>adjective.<DL COMPACT><DD> of or having to do with the mesosphere. </DL>
<A NAME="mesothelial">
<B>mesothelial, </B>adjective.<DL COMPACT><DD> of or having to do with mesothelium. </DL>
<A NAME="mesothelioma">
<B>mesothelioma, </B>noun, pl. <B>-mas,</B> <B>-mata.</B><DL COMPACT><DD> a malignant tumor of the mesothelial tissue of the pleura or peritoneum, usually associated with excessive exposure to asbestos. </DL>
<A NAME="mesothelium">
<B>mesothelium, </B>noun, pl. <B>-liums,</B> <B>-lia.</B><DL COMPACT><DD> that part of the mesoderm that lines the primitive body cavity of a vertebrate embryo. </DL>
<A NAME="mesothermal">
<B>mesothermal, </B>adjective.<DL COMPACT><DD> of or having to do with a moderate or intermediate temperature range. </DL>
<A NAME="mesothoracic">
<B>mesothoracic, </B>adjective.<DL COMPACT><DD> of or having to do with the mesothorax of an insect. </DL>
<A NAME="mesothorax">
<B>mesothorax, </B>noun, pl. <B>-raxes,</B> <B>-races.</B><DL COMPACT><DD> the middle of the three divisions of the thorax of an insect, typically bearing the first pair of wings and the middle pair of legs. </DL>
<A NAME="mesothorium">
<B>mesothorium, </B>noun.<DL COMPACT><DD> either of two radioactive isotopes, mesothorium I (<I>at.no.:</I> 88; <I>half-life:</I> 6.7 years), an isotope of radium, formed from thorium and yielding mesothorium II (<I>at.no.:</I> 89; <I>half-life:</I> 6.13 hours), an isotope of actinium. Both isotopes have an atomic weight of 228, and are intermediate between thorium and radiothorium. </DL>
<A NAME="mesotron">
<B>mesotron, </B>noun. <B>=meson.</B></DL>
<A NAME="mesovarium">
<B>mesovarium, </B>noun.<DL COMPACT><DD> the fold of peritoneum that suspends the ovary. </DL>
<A NAME="mesozoic">
<B>Mesozoic, </B>noun, adjective.<DL COMPACT><DD><I>noun </I> <B>1. </B>the geological era before the present era; Age of Reptiles. It was characterized by the development of mammals, flying reptiles, birds, and flowering plants, and the appearance and death of dinosaurs. It comprises the Triassic, Jurassic, and Cretaceous periods. The Mesozoic began about 225 million years ago. <DD><B> 2. </B>the rocks formed in this era. <DD><I>adj. </I> of this era or these rocks. </DL>
<A NAME="mespil">
<B>mespil, </B>noun. <B>=medlar.</B></DL>
<A NAME="mesquite">
<B>mesquite</B> or <B>mesquit, </B>noun.<DL COMPACT><DD><B> 1. </B>a deep-rooted tree or shrub, common in the southwestern United States and Mexico, that often grows in dense clumps or thickets; algarroba. It belongs to the pea family. Its beanlike pods contain much sugar, and furnish a valuable food for cattle. Its wood is used as fuel and lumber. <BR> <I>Ex. Here and there are patches of a lush green shrub--the mesquite (Scientific American).</I> <DD><B> 2. </B>any closely related plant, especially the screw bean. </DL>
<A NAME="mess">
<B>mess, </B>noun, verb.<DL COMPACT><DD><I>noun </I> <B>1a. </B>a dirty or untidy mass or group of things; dirty or untidy condition. <BR> <I>Ex. Look what a mess you have made of your dress, playing in that dirt. The children kept the house in a mess.</I> <DD><B> b. </B>(Informal.) a person or thing in a poor or untidy condition. <BR> <I>Ex. "Isn't he a mess," said Melanie. The wall had scraped raw patches on Edward's forehead and palms and shins (Joanna Ostrow). In 1914 Russia was, politically and economically, a mess (Colin Simpson).</I> <DD><B> 2. </B>confusion or difficulty. <BR> <I>Ex. His business affairs are in a mess.</I> <DD><B> 3. </B>(Figurative.) an unpleasant or unsuccessful affair or state of affairs. <BR> <I>Ex. He made a mess of his final examinations. Then maybe he would a locked her up, and this awful mess wouldn't ever happened (Mark Twain).</I> <DD><B> 4a. </B>a group of people who take meals together regularly, especially such a group in the armed forces. <BR> <I>Ex. The sailor found the mess a congenial lot.</I> <DD><B> b. </B>a meal for such a group. <BR> <I>Ex. The officers are at mess now.</I> <DD><B> c. </B>a place where such a group eats; mess hall. <BR> <I>Ex. When he is not dining out, he eats in the White House mess (Time).</I> <DD><B> 5a. </B>a portion of food, especially a portion of soft food. <BR> <I>Ex. a mess of oatmeal.</I> <DD><B> b. </B>a quantity of some edible item sufficient for a meal or meals. <BR> <I>Ex. He caught a large mess of fish.</I> <DD><B> 6. </B>food that does not look or taste good. <BR> <I>Ex. The first edge of hunger blunted, I perceived I had got in hand a nauseous mess (Charlotte Bronte).</I> <DD><B> 7. </B>(Informal.) a lot, especially a disagreeable or bothersome lot. <BR> <I>Ex. How about cleanin' up de whole mess of 'em and sta'tin' all over ag'in wid some new kind of animal? (Marc Connelly).</I> <DD><I>v.t. </I> <B>1. </B>to make dirty or untidy. <BR> <I>Ex. He messed up his book by scribbling on the pages.</I> <DD><B> 2. </B>to make a failure of; spoil. <BR> <I>Ex. He messed up his chances of winning the race.</I> <DD><B> 3. </B>to supply with meals, as soldiers or sailors. <DD><I>v.i. </I> to take one's meals (with). <BR> <I>Ex. We turned in to bunk and mess with the crew forward (Richard H. Dana).</I> <BR><I>expr. <B>mess about</B> or <B>around,</B> </I>to busy oneself without seeming to accomplish anything. <BR> <I>Ex. On my vacation I read and messed about with my stamp collection. I mess about my flowers and read snatches of French (Lynn Linton).</I> <BR><I>expr. <B>mess around</B> (or <B>about</B>) <B>with,</B> </I>(Informal.) to tamper with. <BR> <I>Ex. I don't want the school messing around in something I have been doing (Sheila H. Kieran). [She] is determined that one piece of tradition shall not be messed about with (Manchester Guardian).</I> </DL>
