| HETEROCHROMOUS | • heterochromous adj. (Botany) Having the central florets of a flower head of a different colour from those of the circumference. • HETEROCHROMOUS adj. having different colors. | 
| HETEROCHRONOUS | • heterochronous adj. (Paleontology) formed at different periods. • HETEROCHRONOUS adj. divergent from the normal time sequence. | 
| HETEROMORPHOUS | • heteromorphous adj. (Biology) heteromorphic. • HETEROMORPHOUS adj. having different forms, also HETEROMORPHIC. | 
| HYPOMENORRHOEA | • hypomenorrhoea n. Alternative form of hypomenorrhea. • HYPOMENORRHOEA n. the condition in which the interval between two menstrual periods is increased to between 35 and 42 days, also HYPOMENORRHEA. | 
| ORTHOPYROXENES | • orthopyroxenes n. Plural of orthopyroxene. • ORTHOPYROXENE n. a member of the pyroxene group of minerals having an orthorhombic crystal structure, such as enstatite and hypersthene. | 
| OSTEOARTHROSES | • osteoarthroses n. Plural of osteoarthrosis. • OSTEOARTHROSIS n. chronic noninflammatory disease of the joints and the bone adjacent. | 
| PHOTORECEPTORS | • photoreceptors n. Plural of photoreceptor. • PHOTORECEPTOR n. a receptor for light stimuli. | 
| PYROPHOTOMETER | • PYROPHOTOMETER n. a type of pyrometer in which the temperature of an incandescent body is determined by photometric measurement of the light it emits. | 
| TROPHONEUROSES | • trophoneuroses n. Plural of trophoneurosis. • TROPHONEUROSIS n. a state of deranged nutrition owing to disorder of the trophic action of the nerves. | 
| TROUBLESHOOTER | • troubleshooter n. A person skilled at locating the causes of problems and rectifying them. • troubleshooter n. (Computing) A software program or routine that attempts to diagnose a problem with the system. • TROUBLESHOOTER n. a skilled worker employed to locate trouble and make repairs in machinery and technical equipment. | 
| ZOOGEOGRAPHERS | • zoogeographers n. Plural of zoogeographer. • ZOOGEOGRAPHER n. a student of zoogeography. |