[ buhg ]
See synonyms for bug on Thesaurus.com
  1. Also called true bug, hemipteran, hemipteron . a hemipterous insect.

  2. (loosely) any insect or insectlike invertebrate.

  1. Informal. any microorganism, especially a virus: He was laid up for a week by an intestinal bug.

  2. Informal. a defect or imperfection, as in a mechanical device, computer program, or plan; glitch: The test flight discovered the bugs in the new plane.

  3. Informal.

    • a person who has a great enthusiasm for something; fan or hobbyist: My wife is a real adventure bug, so we had a pretty thrilling, action-packed holiday.

    • a craze or obsession: He's got the sports-car bug.

  4. Informal.

    • a hidden microphone or other electronic eavesdropping device.

    • any of various small mechanical or electrical gadgets, as one to influence a gambling device, give warning of an intruder, or indicate location.

  5. a mark, as an asterisk, that indicates a particular item, level, etc.

  6. Horse Racing. the five-pound weight allowance that can be claimed by an apprentice jockey.

  7. a telegraph key that automatically transmits a series of dots when moved to one side and one dash when moved to the other.

  8. Poker Slang. a joker that can be used only as an ace or as a wild card to fill a straight or a flush.

  9. Printing. a label printed on certain matter to indicate that it was produced by a union shop.

  10. any of various fishing plugs resembling an insect.

  11. Chiefly British. a bedbug.

verb (used with object),bugged, bug·ging.Informal.
  1. to install a secret listening device in (a room, building, etc.) or on (a telephone or other device): The phone had been bugged.

  2. to bother; annoy; pester: She's bugging him to get her into show business.

Verb Phrases
  1. bug off, Slang. to leave or depart, especially rapidly: I can't help you, so bug off.

  2. bug out, Slang. to flee in panic; show panic or alarm.

Idioms about bug

  1. put a bug in someone's ear, to give someone a subtle suggestion; hint: We put a bug in his ear about a new gymnasium.

Origin of bug

First recorded in 1615–25; 1885–90 for def. 4; 1910–15 for def. 5a; 1915–20 for def. 14; 1945–50 for def. 15; earlier bugge “beetle,” apparently alteration of Middle English budde, Old English -budda “beetle”; the sense “leave” (in bug off) is obscurely related to other senses and perhaps is of distinct origin

Other words for bug

Other words from bug

  • un·bugged, adjective

Other definitions for bug (2 of 3)

[ buhg ]

  1. a bogy; hobgoblin.

Origin of bug

First recorded in 1350–1400; Middle English bugge “scarecrow, demon, hobgoblin”; further origin unknown

Other definitions for Bug (3 of 3)

[ buhg; Polish, Russian book ]

  1. Also called Western Bug . a river in E central Europe, rising in W Ukraine and forming part of the boundary between Poland and Ukraine, flowing NW to the Vistula River in Poland. 450 miles (725 km) long.

  2. Also called Southern Bug . a river in SW Ukraine flowing SE to the Dnieper estuary. About 530 miles (850 km) long.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use bug in a sentence

British Dictionary definitions for bug (1 of 4)


/ (bʌɡ) /

  1. any insect of the order Hemiptera, esp any of the suborder Heteroptera, having piercing and sucking mouthparts specialized as a beak (rostrum): See also assassin bug, bedbug, chinch bug

  2. mainly US and Canadian any insect, such as the June bug or the Croton bug

  1. informal

    • a microorganism, esp a bacterium, that produces disease

    • a disease, esp a stomach infection, caused by a microorganism

  2. informal an obsessive idea, hobby, etc; craze (esp in the phrases get the bug, be bitten by the bug, the bug bites, etc)

  3. informal a person having such a craze; enthusiast

  4. (often plural) informal an error or fault, as in a machine or system, esp in a computer or computer program

  5. informal a concealed microphone used for recording conversations, as in spying

  6. US (in poker) a joker used as an ace or wild card to complete a straight or flush

verbbugs, bugging or bugged informal
  1. (tr) to irritate; bother

  2. (tr) to conceal a microphone in (a room, etc)

  1. (intr) US (of eyes) to protrude

Origin of bug

C16: of uncertain origin; perhaps related to Old English budda beetle

British Dictionary definitions for bug (2 of 4)


/ (bʌɡ) /

  1. obsolete an evil spirit or spectre; hobgoblin

Origin of bug

C14 bugge, perhaps from Middle Welsh bwg ghost. See also bugbear, bugaboo

British Dictionary definitions for bug (3 of 4)


/ (bʌɡ) /

  1. a past tense and past participle of big 2

British Dictionary definitions for Bug (4 of 4)


/ (Russian buk) /

  1. Also called: Southern Bug a river in E Europe, rising in W Ukraine and flowing southeast to the Dnieper estuary and the Black Sea. Length: 853 km (530 miles)

  2. Also called: Western Bug a river in E Europe, rising in SW Ukraine and flowing northwest to the River Vistula in Poland, forming part of the border between Poland and Ukraine. Length: 724 km (450 miles)

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for bug


[ bŭg ]

  1. An insect belonging to the suborder Heteroptera. See more at true bug.

  2. An insect, spider, or similar organism. Not in scientific use.

usage For bug

The word bug is often used to refer to tiny creatures that crawl along, such as insects and even small animals that are not insects, such as spiders and millipedes. But for scientists the word has a much narrower meaning. In the strictest terms bugs are those insects that have mouthparts adapted for piercing and sucking. The mouthparts of these bugs are contained in a beak-shaped structure. Thus scientists would classify a louse but not a beetle or a cockroach as a bug. In fact, scientists often call lice and their relatives true bugs to distinguish them better from what everyone else calls “bugs.”

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for bug


A generic term that describes a malfunction of undetermined origin in a computer or other electronic device.

Notes for bug

The term originated in the 1940s when the examination of a large computer revealed that an actual insect had landed on one of the circuits, shorting it out and shutting the machine down.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Other Idioms and Phrases with bug


In addition to the idioms beginning with bug

  • bug off
  • bug out

also see:

  • cute as a button (bug's ear)
  • put a bug in someone's ear
  • snug as a bug in a rug
  • what's eating (bugging) you

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.