# bug

Pronunciation: say "BUG" /bʌɡ/

## Noun

1. An insect, spider or other small crawling creature, especially one seen as a pest. *(colloquial)*
   - Simple: Any small insect or creepy-crawly, like a beetle, ant or spider, often one that is a nuisance.
   - _Farmers spray their crops to keep destructive bugs from ruining the harvest._
   - _A single bug in the pantry can quickly turn into an infestation._
2. A flaw or error in software or a system that causes it to behave incorrectly and needs fixing.
   - Simple: A mistake in a computer program or machine that stops it from working the way it should.
   - _A bug in the payment module charged some customers twice._
   - _The team spent all night tracking down bugs before the release._
4. A contagious illness, or the germ or pathogen that causes it.
   - Simple: An illness you can catch from other people, or the germ that causes it.
   - _She picked up a bug on the flight home and spent the week in bed._
   - _A flu-like bug spread quickly through the dormitory._
5. Any insect belonging to the order Hemiptera, whose members are known as true bugs.
   - Simple: A kind of insect, such as an aphid or cicada, that sucks juices from plants or animals.
   - _A bug in this order pierces plant tissue with its beak to drink sap._
   - _Entomologists count aphids and cicadas among the true bugs._
6. A strong enthusiasm for something, sometimes amounting to an obsession. *(colloquial)*
   - Simple: A strong interest in something that takes over your attention.
   - _The collecting bug took hold, and soon his shelves overflowed with stamps._
   - _After one race, the running bug had her training every day._
9. A concealed electronic device used to secretly listen to or intercept conversations.
   - Simple: A small hidden device used to secretly listen to what people say.
   - _Investigators swept the room and discovered a bug behind the painting._
   - _The journalist suspected a bug had been planted in her car._
8. A microorganism of any kind, especially a bacterium, harmful or not, including the helpful ones that live in the gut. *(colloquial)*
   - Simple: Any tiny living thing too small to see, especially bacteria, including helpful ones like those in your belly.
   - _Your gut is home to trillions of bugs, and most of them do you no harm at all._
   - _The lab grew the bug in a petri dish and found it could break down crude oil._
10. A keen enthusiast or dedicated hobbyist. *(colloquial)*
   - Simple: A person who is very keen on a hobby or activity.
   - _Every car bug in town showed up to admire the vintage models._
   - _A lifelong camera bug, she still develops her own film in a closet darkroom._
14. A small, usually invisible element, often a single-pixel image, placed in a web page or email to record who opens it or what they do.
   - Simple: A tiny hidden image or bit of code in a web page or email that secretly tracks who opens it.
   - _Marketers embedded a bug in the email to learn when each recipient opened it._
   - _Analysts found several tracking bugs hidden across the company's landing pages._
15. Any of various crustaceans, such as a lobster, crayfish, or Moreton Bay bug, in regional or informal use.
   - Simple: A regional or informal name for some shellfish, such as lobsters and crayfish.
   - _The fishermen hauled up a trap full of bugs from the bay._
   - _At the aquarium, a Moreton Bay bug lay half-buried in the sand of its tank._
16. A small, usually translucent logo placed in a corner of a TV program to identify the network or channel.
   - Simple: A small see-through logo shown in a corner of the screen to show which channel you are watching.
   - _The network's bug stayed in the lower-right corner throughout the broadcast._
   - _Fans complained that the bug blocked part of the on-screen score._
17. An informal name, chiefly in LGBTQ communities, for HIV, the virus that can cause AIDS.
   - Simple: A slang name for HIV, the virus that can cause AIDS.
   - _Several friends in the community had already contracted the bug by the late 1980s._
   - _He has carried the bug for twenty years, and thanks to modern antiretroviral drugs his viral load is now undetectable._
18. A small emblem printed on a product to show it was produced by unionized labor; a union bug.
   - Simple: A small printed symbol showing that a printed item was made by union workers.
   - _The printed program displayed a bug confirming union production._
   - _The campaign insisted that every yard sign carry the union bug, proof it had been printed in a union shop._
19. A trilobite: an extinct marine arthropod with a segmented, three-lobed exoskeleton. *(slang)*
   - Simple: An extinct sea creature with a hard, segmented shell, known today only from fossils.
   - _He spent the afternoon splitting shale and finally freed a trilobite, his first complete bug of the season._
   - _The museum's drawers were full of bugs collected from Cambrian deposits._
21. A marker that a pilot positions by hand on a flight instrument to flag a reference value.
   - Simple: A marker a pilot moves by hand on a dial to mark an important number.
   - _Before approach, the captain set the bug to the target airspeed._
   - _He nudged the bug around the dial to match the assigned heading._
23. An asterisk printed beside an apprentice jockey's name to denote the weight allowance they receive. *(slang, US)*
   - Simple: A star mark printed by a young jockey's name to show they carry less weight.
   - _The racing form carried a bug after the rookie's name._
   - _In the racing program, the little bug beside the rider's name told bettors he was an apprentice with a weight break._
24. A young apprentice jockey, one still early in a riding career. *(slang, US)*
   - Simple: A young rider who is still learning to be a jockey and gets a weight break.
   - _The stable's promising bug won three races in his debut month._
   - _Veterans often mentor a bug during their first season on the track._
25. A limited form of wild card used in some variants of poker.
   - Simple: A special card in some poker games that works only as a limited wild card.
   - _With four hearts and the bug in his hand, he already had a flush and declined to draw._
   - _The house rules let the bug fill any flush but nothing else._
26. A semi-automatic telegraph key that generates a stream of Morse dots mechanically, letting an operator send code faster with less hand strain.
   - Simple: A special telegraph key that sends Morse code dots automatically to make sending faster.
   - _Veteran telegraphers swore by the bug for high-speed traffic._
   - _He adjusted the bug's contact spacing before the morning schedule._
27. A small metal device that, once fitted inside a slot machine, stops certain winning combinations from appearing. *(slang)*
   - Simple: A small metal part placed inside a slot machine to stop certain winning lineups.
   - _The operator rigged the payout by installing a bug._
   - _Opening the machine, the inspector found a small metal bug fitted so that the top-paying combination could never land._
28. A metal clip fastened to the underside of a table or similar surface to hold hidden cards as a means of cheating. *(slang)*
   - Simple: A metal clip fixed under a table to hide cards, used for cheating in card games.
   - _He palmed the card and tucked it into the bug between hands._
   - _The dealer's bug let him swap cards without anyone noticing._

## Verb

3. To annoy or irritate someone. *(colloquial)*
   - Simple: To bother or annoy someone.
   - _Her little comments started to bug everyone at the table._
   - _It bugged him that no one had told him the news._
7. To install one or more concealed listening devices in a place or object.
   - Simple: To put a hidden listening device inside a room, phone, or other place.
   - _The agency bugged the embassy lounge during the renovations._
   - _They planned to bug his car without anyone noticing._
11. Of the eyes, to bulge or protrude, especially in surprise or strain.
   - Simple: Of eyes, to open very wide and stick out, especially in shock.
   - _His eyes bugged when the final score flashed on the screen._
   - _Her eyes bug out whenever a spider runs across the floor._
13. To behave suspiciously or irrationally, especially in a way that bothers other people. *(colloquial)*
   - Simple: To behave in a strange, jumpy, or annoying way.
   - _My roommate can bug pretty hard when he's stressed, accusing us of moving his stuff and listening at his door._
   - _After three nights without sleep he was really bugging, checking the locks again and again and jumping at every noise._
22. To represent a value by setting a bug, a movable index marker, on an instrument's dial.
   - Simple: To set a marker on a dial or gauge to show a chosen value.
   - _He bugged the decision height on the altimeter during the approach briefing._
   - _Always bug the go-around altitude before you begin the descent._

## Noun

12. A bedbug; a small wingless insect that infests beds and bedding and feeds on human blood. *(dated, UK)*
   - Simple: A bedbug: a small biting insect that hides in beds and feeds on blood.
20. A hobgoblin or bogey; by extension, anything that inspires dread or terror. *(obsolete)*
   - Simple: An imaginary creature or thing that frightens people, like a goblin or scary figure.

## Other meanings

- (noun) In oil prospecting, a tiny fossil such as a foraminifer, studied to identify rock layers.

## Origin

The word in this form is first recorded around 1620, meaning "bedbug." It developed from the earlier bugge ("beetle"), perhaps from Middle English bugge ("scarecrow, hobgoblin"). Where that came from is uncertain. Some trace it to a Celtic root (compare Scots bogill, "goblin," and obsolete Welsh bwg, "ghost"), some to Proto-Germanic *bugja- ("swollen up, thick") and Proto-Indo-European *bʰew- ("to swell"), and some to a word related to buck. Middle English budde ("beetle") may have strengthened the insect meaning. Using bug for a technical fault goes back at least to the 19th century, earlier than the familiar story of a moth found in a computer.

Source: DictionaryAI, https://dictionaryai.com/define/bug (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).