a measuring instrument that sends out an acoustic pulse in water and measures distances in terms of the time for the echo of the pulse to return; "sonar is an acronym for sound navigation ranging"; "asdic is an acronym for antisubmarine detection investigation committee"
condition of heightened watchfulness or preparation for action; "bombers were put on alert during the crisis"
very attentive or observant; "an alert and responsive baby is a joy"; "caught by a couple of alert cops"; "alert enough to spot the opportunity when it came"; "constantly alert and vigilant, like a sentinel on duty"
(usually followed by `to') showing acute awareness; mentally perceptive; "alert to the problems"; "alive to what is going on"; "awake to the dangers of her situation"; "was now awake to the reality of his predicament"
not unconscious; especially having become conscious; "the patient is now awake and alert"
eellike aquatic North American salamander with small forelimbs and no hind limbs; have permanent external gills
an acoustic device producing a loud often wailing sound as a signal or warning
a warning signal that is a loud wailing sound
a sea nymph (part woman and part bird) supposed to lure sailors to destruction on the rocks where the nymphs lived; "Odysseus ordered his crew to plug their ears so they would not hear the Siren's fatal song"
the act of delivering a blow with the foot; "he gave the ball a powerful kick"; "the team's kicking was excellent"
a rhythmic thrusting movement of the legs as in swimming or calisthenics; "the kick must be synchronized with the arm movements"; "the swimmer's kicking left a wake behind him"
the sudden stimulation provided by strong drink (or certain drugs); "a sidecar is a smooth drink but it has a powerful kick"
make a goal; "He kicked the extra point after touchdown"
stop consuming; "kick a habit"
strike with the foot; "The boy kicked the dog"; "Kick the door down"
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
the act of firing weapons or artillery at an enemy; "hold your fire until you can see the whites of their eyes"; "they retreated in the face of withering enemy fire"
a fireplace in which a relatively small fire is burning; "they sat by the fire and talked"
intense adverse criticism; "Clinton directed his fire at the Republican Party"; "the government has come under attack"; "don't give me any flak"
the event of something burning (often destructive); "they lost everything in the fire"
a severe trial; "he went through fire and damnation"
the process of combustion of inflammable materials producing heat and light and (often) smoke; "fire was one of our ancestors' first discoveries"
once thought to be one of four elements composing the universe (Empedocles)
bake in a kiln so as to harden; "fire pottery"
cause to go off; "fire a gun"; "fire a bullet"
go off or discharge; "The gun fired"
drive out or away by or as if by fire; "The soldiers were fired"; "Surrender fires the cold skepticism"
terminate the employment of; "The boss fired his secretary today"; "The company terminated 25% of its workers"