air passage provided by a retractable device containing intake and exhaust pipes; permits a submarine to stay submerged for extended periods of time
breathing device consisting of a bent tube fitting into a swimmer's mouth and extending above the surface; allows swimmer to breathe while face down in the water
(American football) a play in which a defensive player is allowed to cross the line of scrimmage and then blocked off as the runner goes through the place the lineman vacated
computer circuit consisting of an electronic sub-assembly; copper conductors are laminated on an insulating board or card and circuit components are inserted into holes and dip soldered
(biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals
a device that delivers an electric current as the result of a chemical reaction
a room where a prisoner is kept
small room is which a monk or nun lives
any small compartment; "the cells of a honeycomb"
a small unit serving as part of or as the nucleus of a larger political movement