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
occurring or existing at the same time or having the same period or phase; "recovery was synchronous with therapy"- Jour.A.M.A.; "a synchronous set of clocks"; "the synchronous action of a bird's wings in flight"; "synchronous oscillations"
(digital communication) pertaining to a transmission technique that requires a common clock signal (a timing reference) between the communicating devices in order to coordinate their transmissions
a spot that is open late at night and that provides entertainment (as singers or dancers) as well as dancing and food and drink; "don't expect a good meal at a cabaret"; "the gossip columnist got his information by visiting nightclubs every night"; "he played the drums at a jazz club"
composition (often improvised) for a solo instrument (especially solo organ) and not a regular part of a religious service or musical performance
of your own free will or design; not forced or compelled; "man is a voluntary agent"; "participation was voluntary"; "voluntary manslaughter"; "voluntary generosity in times of disaster"; "voluntary social workers"; "a voluntary confession"
controlled by individual volition; "voluntary motions"; "voluntary muscles"