From The Collaborative International Dictionary of English v.0.48:
Hushing \Hush"ing\, n. (Mining) The process of washing ore, or of uncovering mineral veins, by a heavy discharge of water from a reservoir; flushing; -- also called booming and hydraulic mining. [1913 Webster +PJC]
From The Collaborative International Dictionary of English v.0.48:
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. [1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
Booming \Boom"ing\, a. 1. Rushing with violence; swelling with a hollow sound; making a hollow sound or note; roaring; resounding. [1913 Webster]
O'er the sea-beat ships the booming waters roar. --Falcone. [1913 Webster]
2. Advancing or increasing amid noisy excitement; as, booming prices; booming popularity. [Colloq. U. S.] [1913 Webster]
From The Collaborative International Dictionary of English v.0.48:
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. [1913 Webster]
At eve the beetle boometh Athwart the thicket lone. --Tennyson. [1913 Webster]
2. To make a hollow sound, as of waves or cannon. [1913 Webster]
Alarm guns booming through the night air. --W. Irving. [1913 Webster]
3. To rush with violence and noise, as a ship under a press of sail, before a free wind. [1913 Webster]
She comes booming down before it. --Totten. [1913 Webster]
4. To have a rapid growth in market value or in popular favor; to go on rushingly. [1913 Webster]