hemi- prefix. ['hɛmi]
[Greek hēmi- combining elem. corresp. to Latin SEMI-, from Indo-European base also of Old English sam- (cf. SAND-BLIND), Old Saxon sām-, Old High German sāmi-.]
Used in words adopted (ult.) from Greek, or as a productive prefix (esp. in scientific and technical subjects) in new formations usu. with Greek roots, with the sense 'half-, affecting one half, partial.' Cf. SEMI-.

■ hemi-'acetal noun (Chemistry) any of a class of compounds of formula RCH(OH)(OR'), differing from acetals in having a hydroxyl instead of one alkoxy-group L19.

■ hemibranch noun (Ichthyology) an incomplete gill, having lamellae on one side only L19.

■ hemi'cellulose noun any of various polysaccharides of simpler composition than cellulose which occur as constituents of the cell walls of plants L19.

■ hemi'chordate noun & adjective (a) noun any member of the phylum Hemichordata of wormlike marine invertebrates, including the acorn worms and pterobranchs and orig. classified as chordates; (b) adjective of or pertaining to this phylum: L19.

■ hemicircle noun a semicircle E17.

■ hemico'lectomy noun (an instance of) surgical removal of the right or left half of the colon E20.

■ hemi'cryptophyte noun (Botany) a plant having perennial shoots and buds at ground level or within the surface layer of soil E20.

■ hemicy'lindrical adjective having the form of half a cylinder M19.

■ hemi'hedral adjective (Crystallography) (of a crystal or crystal class) having half of the maximum number of faces or symmetry planes possible for a given crystal system M19.

■ hemi'hedron noun, pl. -dra, -drons, Crystallography any hemihedral crystal M19.

■ hemi'hedry noun (Crystallography) the property of being hemihedral M19.

■ hemi'hydrate noun (Chemistry) a hydrate containing half a mole of water per mole of the compound L19.

■ hemi'parasite noun (Botany) a parasitic plant which can also live as a saprophyte (as certain fungi), or which also photosynthesizes (as mistletoe) L19.

■ hemipara'sitic adjective pertaining to or of the nature of a hemiparasite E20.

■ hemipa'resis noun = HEMIPLEGIA L19.

■ hemipa'retic adjective = HEMIPLEGIC adjective L19.

■ hemipenis noun (Zoology) each of the paired eversible copulatory organs in snakes and lizards E20.

■ hemisect verb trans. bisect esp. longitudinally or into right and left halves L19.

■ hemi'section noun the action or process of hemisecting L19.

■ hemispasm noun a spasm affecting one side of the body only L19.

■ hemitone noun a semitone L17-M18.

■ hemi'zygote noun (Biology) a hemizygous organism M20.

■ hemi'zygous adjective (Biology) having a single unpaired allele at a particular genetic locus E20.

[TahlilGaran] English Dictionary ▲