| ARRHENOTOKIES | • ARRHENOTOKY n. giving birth only to boys. |
| BACKGROUNDERS | • backgrounders n. Plural of backgrounder. • BACKGROUNDER n. an off the record briefing for reporters. |
| BREAKTHROUGHS | • breakthroughs n. Plural of breakthrough. • BREAKTHROUGH n. an offensive thrust that penetrates and carries beyond a defensive line in warfare. |
| BREASTSTROKER | • breaststroker n. (Swimming) A person swimming using the breaststroke. • BREASTSTROKER n. one who swims using breaststroke. |
| BREASTSTROKES | • breaststrokes n. Plural of breaststroke. • breaststrokes v. Third-person singular simple present indicative form of breaststroke. • BREASTSTROKE n. a swimming-stroke performed breast-down, with circling movements of the arms and a froglike movement of the legs. |
| CHECKERBOARDS | • checkerboards n. Plural of checkerboard. • CHECKERBOARD n. a board used in various games (as checkers) with usually 64 squares in 2 alternating colors. |
| HETEROKARYONS | • heterokaryons n. Plural of heterokaryon. • HETEROKARYON n. a cell, as in the mycelium of a fungus, that contains two or more genetically unlike nuclei. |
| HOUSEBREAKERS | • housebreakers n. Plural of housebreaker. • house-breakers n. Plural of house-breaker. • house␣breakers n. Plural of house breaker. |
| HYDROCRACKERS | • hydrocrackers n. Plural of hydrocracker. • HYDROCRACKER n. one engaged in hydrocracking. |
| KATHAROMETERS | • katharometers n. Plural of katharometer. • KATHAROMETER n. an instrument measuring changes in composition of gases. |
| KERAUNOGRAPHS | • keraunographs n. Plural of keraunograph. • KERAUNOGRAPH n. an instrument for detecting distant thunderstorms, also CERAUNOGRAPH. |
| MASTERSTROKES | • masterstrokes n. Plural of masterstroke. • master␣strokes n. Plural of master stroke. • MASTERSTROKE n. a masterly performance or move. |
| SKATEBOARDERS | • skateboarders n. Plural of skateboarder. • SKATEBOARDER n. one who skateboards. |
| STONEBREAKERS | • stonebreakers n. Plural of stonebreaker. • STONEBREAKER n. a person that breaks up stone; a machine used to break up stone. |
| STRATOTANKERS | • STRATOTANKER n. a type of aeroplane which refuels other planes at high altitudes. |
| TROUBLEMAKERS | • troublemakers n. Plural of troublemaker. • trouble-makers n. Plural of trouble-maker. • trouble␣makers n. Plural of trouble maker. |