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
melt (fat or lard) in order to separate out impurities; "try the yak butter"; "render fat in a casserole"
test the limits of; "You are trying my patience!"
give pain or trouble to; "I've been sorely tried by these students"
make an effort or attempt; "He tried to shake off his fears"; "The infant had essayed a few wobbly steps"; "The police attempted to stop the thief"; "He sought to improve himself"; "She always seeks to do good in the world"
a hypothesis that has been formed by speculating or conjecturing (usually with little hard evidence); "speculations about the outcome of the election"; "he dismissed it as mere conjecture"
an investment that is very risky but could yield great profits; "he knew the stock was a speculation when he bought it"
(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