Source : Webster's Revised Unabridged Dictionary (1913)

Boom \Boom\ (b[=oo]m), v. i. [imp. & p. p. {Boomed}, p. pr. &
   vb. n. {Booming}.] [Of imitative origin; cf. OE. bommen to
   hum, D. bommen to drum, sound as an empty barrel, also W.
   bwmp a hollow sound; aderyn y bwmp, the bird of the hollow
   sound, i. e., the bittern. Cf. {Bum}, {Bump}, v. i., {Bomb},
   v. i.]
   1. To cry with a hollow note; to make a hollow sound, as the
      bittern, and some insects.

            At eve the beetle boometh Athwart the thicket lone.
                                                  --Tennyson.

   2. To make a hollow sound, as of waves or cannon.

            Alarm guns booming through the night air. --W.
                                                  Irving.

   3. To rush with violence and noise, as a ship under a press
      of sail, before a free wind.

            She comes booming down before it.     --Totten.

   4. To have a rapid growth in market value or in popular
      favor; to go on rushingly.

Booming \Boom"ing\, a.
   1. Rushing with violence; swelling with a hollow sound;
      making a hollow sound or note; roaring; resounding.

            O'er the sea-beat ships the booming waters roar.
                                                  --Falcone.

   2. Advancing or increasing amid noisy excitement; as, booming
      prices; booming popularity. [Colloq. U. S.]

Booming \Boom"ing\, n.
   The act of producing a hollow or roaring sound; a violent
   rushing with heavy roar; as, the booming of the sea; a deep,
   hollow sound; as, the booming of bitterns. --Howitt.

Source : WordNet®

booming
     adj 1: very lively and profitable; "flourishing businesses"; "a
            palmy time for stockbrokers"; "a prosperous new
            business"; "doing a roaring trade"; "a thriving
            tourist center"; "did a thriving business in orchids"
            [syn: {flourishing}, {palmy}, {prospering}, {prosperous},
             {roaring}, {thriving}]
     2: used of the voice [syn: {stentorian}]