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boom¹

(bm)

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.

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.]

boomy adj.

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.

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