bug

Definitions

General English

General Science

  • noun a winged insect belonging to the class Hemiptera

Computing

Electronics

  • A persistent error or defect in computer software or hardware. Said especially of one which causes malfunctions.
  • A defect present in a circuit, device, component, or the like, which causes malfunctions. Also called electronic bug (1).
  • An electronic device utilized to surreptitiously listen to and/or record conversations. Also called electronic bug (2).
  • A semiautomatic telegraph key for producing correctly spaced dots and dashes. Also called electronic bug (3).

Law

  • noun a small device which can record conversations secretly and send them to a secret radio receiver
  • verb to place a secret device in a place so that conversations can be heard and recorded secretly

Medical

  • noun an infectious disease

Slang

  • noun (something) excellent, superlative. In the expression ‘it’s the bug!’.
  • verb to irritate or annoy. The image is of a crawling, buzzing or biting insect. The use of this term spread to Britain in the beatnik era but has never fully established itself.

Travel

  • noun a harmful organism, such as a virus, that causes a disease

Origin & History of “bug”

Originally, bug meant ‘something frightening’ – and in fact one of the earliest known uses of the word was for what we would now call a ‘scare-crow’. It is one of a set of words (others are bogle and perhaps bugaboo) for alarming or annoying phenomena, usually supernatural, whose interrelationship and ultimate source have never been adequately explained (see (bogey)).

Bug ‘insect’ (16th c.) is probably the same word, although it has also been connected with Old English budd ‘beetle’. The meanings ‘defect’ (from the 19th century) and ‘germ’ and ‘hidden microphone’ (both 20th-century) all developed from ‘insect’.
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