| holostraca | <zoology> A division of phyllopod Crustacea, including those that are entirely covered by a bivalve shell. Origin: NL, fr. Gr. Whole + shell of a testacean. Source: Websters Dictionary (01 Mar 1998) |
|---|---|
| holosystolic | Lasting throughout systole, extending from first to second heart sound. Synonym: holosystolic. (05 Mar 2000) |
| holosystolic murmur | A murmur occupying the entire systolic interval, from first to second heart sounds. Synonym: holosystolic murmur. (05 Mar 2000) |
| holotelencephaly | Holoprosencephaly associated with arrhinencephaly. Origin: holo-+ telencephalon (05 Mar 2000) |
| holothure | <zoology> A holothurian. Origin: L. Holothuria, pl, a sort of water polyp, Gr. Source: Websters Dictionary (01 Mar 1998) |
| holothurin | <chemical> A highly toxic saponin occurring in the tropical sea cucumber, holothuriodeae, phylum echinodermata. This marine toxin is an anionic surfactant, haemolyzing red blood corpuscles. It acts irreversibly to destroy the excitability at cholinergic neuromuscular junctions. Chemical name: Holothurin (12 Dec 1998) |
| holothurins | A class of highly toxic sulfated steroid glycosides secreted by sea cucumbers (Holothurioidea). (05 Mar 2000) |
| holothurioidea | <zoology> One of the classes of echinoderms. They have a more or less elongated body, often flattened beneath, and a circle of tentacles, which are usually much branched, surrounding the mouth; the skin is more or less flexible, and usually contains calcareous plates of various characteristic forms, sometimes becoming large and scalelike. most of the species have five bands (ambulacra) of sucker-bearing feet along the sides; in others these are lacking. In one group (Pneumonophora) two branching internal gills are developed; in another (Apneumona) these are wanting. Synonym: Holothurida, Holothuridea, and Holothuroidea. Origin: NL. See Holothure, and -oid. Source: Websters Dictionary (01 Mar 1998) |
| holotricha | <zoology> A group of ciliated Infusoria, having cilia all over the body. Origin: NL, fr. Gr. Whole +, a hair. Source: Websters Dictionary (01 Mar 1998) |
| holotrichous | Possessing cilia over the entire surface. Origin: holo-+ G. Thrix, hair (05 Mar 2000) |
| holotype | <zoology> A single specimen designated or indicated the type specimen by the original author at the time of publication of the original description. (09 Jan 1998) |
| holozoic | Animal-like in mode of obtaining nourishment, lacking photosynthetic capacity; denoting certain protozoans, in distinction to others that are holophytic. Origin: holo-+ G. Zoon, animal (05 Mar 2000) |
| holster | A leather case for a pistol, carried by a horseman at the bow of his saddle. Origin: D. Holster; skin to AS. Heolstor den, cave, fr.helan to conceal, and to Icel. Hulstr case, Goth.hulistr covering, veil, huljan to cover. See Hele to cover, Hell, and cf. Housing, Houss. Source: Websters Dictionary (01 Mar 1998) |
| holt | 1. A piece of woodland; especially, a woody hill. "Every holt and heath." "She sent her voice though all the holt Before her, and the park." (Tennyson) 2. A deep hole in a river where there is protection for fish; also, a cover, a hole, or hiding place. " The fox has gone to holt." Origin: AS. Holt; akin to LG.holt, D.hout, G. Holz. Icel. Holt; cf Gael. & Ir.coill wood, Gr. Branch, shoot. Source: Websters Dictionary (01 Mar 1998) |
| Holt-Oram syndrome | <syndrome> An inherited type of heart disease where there are defects in the internal walls (septa) between the atrium and ventricle chambers of the heart. Holt-Oram syndrome is dominant (requires only one copy in the genome to be expressed) and is often associated with skeletal deformities such as abnormally short forearms or thumbs. Inheritance: autosomal dominant. (09 Oct 1997) |