D defs.my
Entry 4 senses Webster, 1913

Boomer

/bo͞om'-ẽr/ · Boom·er · IPA /ˈbumɚ/
01 n. One who, or that which, booms.
  1. 1.
    One who, or that which, booms.
  2. 2.
    A North American rodent, so named because it is said to make a booming noise. See Sewellel.(Zool.) See: Sewellel
  3. 3.
    A large male kangaroo.(Zool.)
  4. 4.
    One who works up a “boom”.[Slang, U. S.]