| AEROTROPISM | • aerotropism n. (Biology) The growth of an organism either towards, or away from a region of higher oxygen content. • aërotropism n. Alternative spelling of aerotropism. • AEROTROPISM n. curvature in response to concentration of oxygen. | 
| AMELIORATOR | • ameliorator n. A person who, or thing which, ameliorates. • AMELIORATOR n. one who ameliorates. | 
| ARTERIOTOMY | • arteriotomy n. (Medicine) The opening of an artery, especially for bloodletting. • ARTERIOTOMY n. the surgical excision of an artery. | 
| ASTRONOMERS | • astronomers n. Plural of astronomer. • ASTRONOMER n. a person who is skilled in astronomy or who makes observations of celestial phenomena. | 
| COTEMPORARY | • cotemporary adj. (Now rare, nonstandard) Alternative form of contemporary. • cotemporary n. (Now rare, nonstandard) Alternative form of contemporary. • COTEMPORARY adj. contemporary, also CONTEMPORARY. | 
| ERGATOMORPH | • ERGATOMORPH n. an ergatoid ant. | 
| GASTRONOMER | • gastronomer n. A lover of good food; a connoisseur or gourmet. • GASTRONOMER n. a connoisseur of good eating and drinking; a gourmet, also GASTROLOGER, GASTRONOME. | 
| MELIORATORS | • meliorators n. Plural of meliorator. • MELIORATOR n. one who meliorates. | 
| METEOROGRAM | • meteorogram n. Synonym of meteogram. • METEOROGRAM n. a meteorograph record. | 
| MOTHERBOARD | • motherboard n. (Computer hardware) The primary circuit board of a personal computer, containing the circuitry for the… • MOTHERBOARD n. the board containing the main circuits of an electronic device, especially in computers. | 
| MOTORBOATER | • motorboater n. Someone who pilots a motorboat. • MOTORBOATER n. one who drives a motorboat. | 
| OSTRACODERM | • ostracoderm n. (Zoology) Any of the armored jawless fishes of the Paleozoic. • OSTRACODERM n. any of the early fossil jawless fishes of the Lower Paleozoic usually having a bony covering of plates or scales. | 
| REFORMATION | • reformation n. An improvement (or an intended improvement) in the existing form or condition of institutions or practices… • reformation n. (Law) Change or correction, by a court in equity, to a written instrument to conform to the original… • Reformation prop.n. (Historical) The religious movement initiated in the 16th century against the Roman Catholic Church. | 
| REFORMATORY | • reformatory adj. Of, pertaining to, or conducive to reform; reformative. • reformatory n. A prison, especially one for juveniles; a reform school. • REFORMATORY n. a penal institution to which esp. young or first offenders are committed for training and reformation. | 
| TAMPERPROOF | • tamperproof adj. Resistant to tampering. • tamperproof v. (Transitive) To make resistant to tampering. • TAMPERPROOF adj. proof against tampering. |