1.A bugbear; anything which terrifies. (Obs.) "Sir, spare your threats: The bug which you would fright me with I seek."
2.(Zool.) A general name applied to various insects belonging to the Hemiptera; as, the squash bug; the chinch bug, etc.
4.(Zool.) One of various species of Coleoptera; as, the ladybug; potato bug, etc.; loosely, any beetle.
5.(Zool.) One of certain kinds of Crustacea; as, the sow bug; pill bug; bait bug; salve bug, etc. Note: According to popular usage in England and among housekeepers in America around 1900, bug, when not joined with some qualifying word, was used specifically for bedbug. As a general term it is now used very loosely in America as a colloquial term to mean any small crawling thing, such as an insect or arachnid, and was formerly used still more loosely in England. "God's rare workmanship in the ant, the poorest bug that creeps." (). "This bug with gilded wings."
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.) Note: In some communities in the 1990's, the incidence of AIDS is high and AIDS is referred to colloquially as "the bug".
11.An enthusiast; used mostly in combination, as a camera bug. (Colloq.)
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