a loud, deep, resonant sound

the deep boom of the bass drum

make a loud, deep, resonant sound

thunder boomed in the sky

used to imitate a loud, deep, resonant sound

the boat was lifted up and then boom, down it went

a period of great prosperity or rapid economic growth

the London property boom

experience a period of great prosperity or rapid economic growth

business is booming

a pivoted spar to which the foot of a vessel's sail is attached, allowing the angle of the sail to be changed

a movable arm over a television or film set, carrying a microphone or camera

a boom mike

a floating beam used to contain oil spills or to form a barrier across the mouth of a harbour or river