I. adjective
( -er/-est )
Etymology: from present participle of boom (III)
1. : making or performing an action with a booming sound
his booming voice
the booming river
2. : increasing or growing rapidly
a booming railroad center
booming wheat prices
• boom·ing·ly adverb
II. noun
( -s )
Etymology: from gerund of boom (III)
1. : the sound or act of one that booms
2. : the process of discharging water behind a dam down a hillside or gorge to wash out deposits of gold