| black widow spider | A venomous new world spider with an hourglass-shaped red mark on the abdomen. (12 Dec 1998) |
|---|---|
| black widow spider venom | Potent neurotoxin that induces catastrophic release of acetylcholine from presynaptic terminals of cholinergic chemical synapses. (18 Nov 1997) |
| vascular spider | spider angioma |
| water spider | <zoology> An aquatic European spider (Argyoneta aquatica) which constructs its web beneath the surface of the water on water plants. It lives in a bell-shaped structure of silk, open beneath like a diving bell, and filled with air which the spider carries down in the form of small bubbles attached one at a time to the spinnerets and hind feet. Synonym: diving spider. A water mite. Any spider that habitually lives on or about the water, especially the large American species (Dolomedes lanceolatus) which runs rapidly on the surface of water. Synonym: raft spider. Source: Websters Dictionary (01 Mar 1998) |
| sea spider | <zoology> Any maioid crab; a spider crab. See Maioid, and Spider crab, under Spider. Any pycnogonid. Source: Websters Dictionary (01 Mar 1998) |
| spider | 1. <zoology> Any one of numerous species of arachnids comprising the order Araneina. Spiders have the mandibles converted into poison fangs, or falcers. The abdomen is large and not segmented, with two or three pairs of spinnerets near the end, by means of which they spin threads of silk to form cocoons, or nests, to protect their eggs and young. Many species spin also complex webs to entrap the insects upon which they prey. The eyes are usually eight in number (rarely six), and are situated on the back of the cephalothorax. Spiders are divided into two principal groups: the Dipneumona, having two lungs: and the Tetrapneumona, having four lungs. See Mygale. The former group includes several tribes; as, the jumping spiders (see Saltigradae), the wolf spiders, or Citigradae (see under Wolf), the crab spiders, or Laterigradae (see under Crab), the garden, or geometric, spiders, or Orbitellae (see under Geometrical, and Garden), and others. See Bird spider, Grass spider, House spider, Silk spider. 2. <zoology> Any one of various other arachnids resembling the true spiders, especially certain mites, as the red spider (see under Red). 3. An iron pan with a long handle, used as a kitchen utensil in frying food. Originally, it had long legs, and was used over coals on the hearth. 4. A trevet to support pans or pots over a fire. 5. <machinery> A skeleton, or frame, having radiating arms or members, often connected by crosspieces; as, a casting forming the hub and spokes to which the rim of a fly wheel or large gear is bolted; the body of a piston head; a frame for strengthening a core or mold for a casting, etc. Spider ant. Any one of numerous species of South American monkeys of the genus Ateles, having very long legs and a long prehensile tail. <botany> Spider orchis, any shell of the genus Pteroceras. See Pteroceras. Origin: OE. Spire, fr. AS. Spinnan to spin; so named from spinning its web; cf. D. Spin a spider, G. Spinne, Sw. Spindel. Seee Spin. Source: Websters Dictionary (01 Mar 1998) |
| spider angiomas | A branched growth of dilated capillaries on the skin, resembling a spider. This abnormality may be associated with cirrhosis of the liver. (27 Sep 1997) |
| spider-burst | Radiating dull red capillary lines on the skin of the leg, usually without any visible or palpable varicose veins, but nevertheless due to deep-seated venous dilation; sometimes referred to as skyrocket capillary ectasis. Origin: spiderweb + sunburst (05 Mar 2000) |
| spider cancer | An obsolete term for a malignant neoplasm with a rhizoid or filamentous edge of thin, threadlike, red lines that represent dilated vascular channels associated with the neoplasm; a form of telangiectatic cancer. (05 Mar 2000) |
| spider cell | <pathology> A glial cell found in vertebrate brain, named for its characteristic star like shape. Astrocytes lend both mechanical and metabolic support for neurons, regulating the environment in which they function. See: oligodendrocytes. (18 Nov 1997) |
| spider finger | <clinical sign> A skeletal disorder where the patient has unusually long, thin bones, especially noticeable in the fingers and toes. (09 Oct 1997) |
| spider haemangioma | spider angioma |
| spider mole | spider angioma |
| spider nevus | A branched growth of dilated capillaries on the skin, resembling a spider. This abnormality may be associated with cirrhosis of the liver. (27 Sep 1997) |
| spider pelvis | Narrow calices of renal pelvis. (05 Mar 2000) |