Dictionary definition · boom
noun
- a deep prolonged loud noise
- a state of economic prosperity
- a sudden happening that brings good fortune (as a sudden opportunity to make money)"the demand for testing has created a boom for those unregulated laboratories where boxes of specimen jars are processed like an assembly line"
- a pole carrying an overhead microphone projected over a film or tv set
- any of various more-or-less horizontal spars or poles used to extend the foot of a sail or for handling cargo or in mooring
verb
- make a resonant sound, like artillery"His deep voice boomed through the hall"
- hit with great force"He smashed a 3-run homer"
- be the case that thunder is being heard"Whenever it thunders, my dog crawls under the bed"
- make a deep hollow sound"Her voice booms out the words of the song"
- grow vigorously"The deer population in this town is thriving"
Source: Open English WordNet (CC BY 4.0).