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boom 1 (bm)
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v. boomed, boom·ing, booms
v.intr.
1. To make a deep, resonant sound.
2. To grow, develop, or progress rapidly; flourish: Business is booming.
v.tr.
1. To utter or give forth with a deep, resonant sound: a field commander booming out orders.
2. To cause to grow or flourish; boost.
n.
1. A deep resonant sound, as of an explosion.
2. A time of economic prosperity.
3. A sudden increase, as in popularity.

[Middle English bomben, imitative of a loud noise.]

boomy adj.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
boom 2 (bm)
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n.
1. Nautical A spar extending usually from a mast to hold the foot, clew, or tack of a sail.
2. A long pole extending upward at an angle from the mast of a derrick to support or guide objects being lifted or suspended.
3.
a. A barrier composed of a chain of floating logs, typically used to block the passage of boats or to arrest the downstream motion of logs in a log drive.
b. A floating barrier serving to catch debris or to contain an oil spill.
4. A long movable arm used to maneuver and support a microphone.
5.
a. A spar that connects the tail surfaces and the main structure of an airplane.
b. A long hollow tube attached to a tanker aircraft, through which fuel flows to another aircraft being refueled in flight.
tr.v. boomed, boom·ing, booms
To move or position using a crane: boomed the cargo onto the ship.
Idiom:
drop/lower the boom
To act suddenly and forcefully to repress a practice or reprimand an offender; crack down.

[Dutch, tree, pole, from Middle Dutch; see bheuə- in the Appendix of Indo-European roots.]
(click for a larger image)
boom2
contamination containment booms

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.