bug

1 of 4

noun (1)

ˈbəg

: any of an order (Hemiptera and especially its suborder Heteroptera) of insects (such as an assassin bug or chinch bug) that have sucking mouthparts, forewings thickened at the base, and incomplete metamorphosis and are often economic pests

called also true bug

: any of various small arthropods (such as a beetle or spider) resembling the true bugs

: any of several insects (such as a head louse) commonly considered obnoxious

: an unexpected defect, fault, flaw, or imperfection

the software was full of bugs

: a microorganism (such as a bacterium or virus) especially when causing illness or disease

: an often unspecified or nonspecific sickness presumed to be caused by such a microorganism

a stomach bug

: a concealed listening device

: a sudden enthusiasm

: enthusiast

a camera bug

: a prominent person

: a crazy person

[from its designation by an asterisk on race programs] : a weight allowance given apprentice jockeys

bug

2 of 4

verb (1)

bugged; bugging

transitive verb

: bother, annoy

don't bug me with petty details

: to plant a concealed microphone in

intransitive verb

: to lose one's composure : freak

—often used with out

bug

3 of 4

verb (2)

bugged; bugging

intransitive verb

of the eyes : protrude, bulge

—often used with out

transitive verb

of the eyes : to cause to bug

his eyes were bugged with horror

bug

4 of 4

noun (2)

obsolete

: bogey, bugbear

Word History

Etymology

Noun (1)

origin unknown

Verb (2)

probably from bug entry 1

Noun (2)

Middle English bugge hobgoblin; probably akin to Low German bögge goblin

First Known Use

Noun (1)

1594, in the meaning defined at sense 1b

Verb (1)

1935, in the meaning defined at transitive sense 2

Verb (2)

1865, in the meaning defined at transitive sense

Noun (2)

15th century, in the meaning defined above

Time Traveler

The first known use of bug was in the 15th century

See more words from the same century

Articles Related to bug

The Difference Between 'Bug,' 'Insect,'...

A bug is an insect and so is a beetle, so what's an insect?

snug as a bug in a rug dogs under blanket

Uncovering 'Snug as a Bug In a Rug'

'Snug' is nautical; 'bug' refers to a hobgoblin; 'rug,' a blanket.

Words for Mistakes

Find the mot juste for your misstep

Cite this Entry

Style

“Bug.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bug. Accessed 26 Jan. 2023.

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Kids Definition

bug

1 of 2 noun

ˈbəg

: an insect (as a beetle) or other creeping or crawling invertebrate animal (as a centipede)

: any of an order of insects (as bedbugs and stinkbugs) that have sucking mouthparts and the forewings part leathery and part membranous and that undergo incomplete metamorphosis

called also true bug

: an unexpected mistake or imperfection

a bug in a computer program

: a disease-producing germ

also : a disease caused by it

: fan entry 3, enthusiast

a camera bug

: a concealed listening device

bug

2 of 2 verb

bugged; bugging

: to place a concealed microphone in

: bother entry 1 sense 1, annoy

: freak entry 3

—usually used with out

Medical Definition

bug

noun

ˈbəg

: an insect or other creeping or crawling invertebrate animal (as a spider)

—not used technically

: any of various insects (as the bedbug or cockroach) commonly considered obnoxious

: any of the order Hemiptera and especially of its suborder Heteroptera of insects that have sucking mouthparts, forewings thickened at the base, and that lack a pupal stage between the immature stages and the adult

called also true bug

: a microorganism (such as a bacterium or virus) especially when causing illness or disease

Enterococcus faecium, an especially nasty bug, often shrugs off even vancomycin, a last-resort antibiotic.—

Avery Comarow, U.S. News & World Report

: an often unspecified or nonspecific sickness presumed to be caused by such a microorganism

a stomach bug

suffering from the flu bug

Legal Definition

bug

transitive verb

bugged; bugging

: to plant a concealed microphone in compare eavesdrop, wiretap

Geographical Definition

Bug

geographical name

ˈbüg

river over 450 miles (720 kilometers) long in central Europe rising in western Ukraine, forming part of Ukraine–Poland and Poland–Belarus borders, and flowing into the Vistula River in Poland

river over 500 miles (805 kilometers) long in southwestern Ukraine flowing southeast to the estuary of the Dnieper River