Bug /(bŭg)/

Bug

n.
  1. A bugbear; anything which terrifies. [Obs.]
    Sir, spare your threats: The bug which you would fright me with I seek.
  2. A general name applied to various insects belonging to the Hemiptera; as, the squash bug; the chinch bug, etc. (Zool.)
  3. An insect of the genus Cimex, especially the bedbug (Cimex lectularius). See Bedbug. (Zool.)
  4. One of various species of Coleoptera; as, the ladybug; potato bug, etc.; loosely, any beetle. (Zool.)
  5. One of certain kinds of Crustacea; as, the sow bug; pill bug; bait bug; salve bug, etc. (Zool.)
  6. An error in the coding of a computer program, especially one causing the program to malfunction or fail. See, for example, year 2000 bug. (Computers)
  7. Any unexpected defect or flaw, such as in a machine or a plan.
  8. A hidden electronic listening device, used to hear or record conversations surreptitiously.
  9. An infectious microorganism; a germ{4}. [Colloq.]
  10. An undiagnosed illness, usually mild, believed to be caused by an infectious organism. [Colloq.]
  11. An enthusiast; -- used mostly in combination, as a camera bug. [Colloq.]

Phrases & Compounds
Bait bug
See under Bait.
Bug word
swaggering or threatening language.

Bug

v. t.
  1. to annoy; to bother or pester.