Word.ws English Dictionary

heisenbug

/ˈhaɪzənˌbʌɡ/

heisenbug noun: a software bug which fails to manifest itself or manifests differently during debugging.

Noun (1)

heisenbug (plural heisenbugs)

  1. A software bug which fails to manifest itself or manifests differently during debugging.
    • I recently encountered a particularly infuriating Heisenbug. A large program, when given a large input, was just mysteriously dying. Of course, I ran it under the debugger. The mystery deepened: the program returned quietly to the debugger.1987 January 4, Don Lindsay, “More Heisen-debugs”, in RISKS Digest, volume 4, number 36
    • Except for pointer messups in C on my side, the Heisenbugs I've come across were hardly ever caused by _me_.1994 January 20, Heinz Wrobel, “'Heisenbugs'”, in comp.programming (Usenet), message-ID <heinz.0i4s@hwg.muc.de>

Noun (2) capitalized: Heisenbug

Heisenbug (plural Heisenbugs)

  1. Alternative letter-case form of heisenbug.

Forms of heisenbug

pluralheisenbugs
alternative formHeisenbug
pluralHeisenbugs

Origin of heisenbug

(ca. 1983) Blend of Heisenberg + bug. Named for the Heisenberg uncertainty principle, which states very roughly that any attempt to measure the position of a subatomic particle will disrupt its movement, making it harder to predict.

Questions about heisenbug

What does heisenbug mean?
Heisenbug means a software bug which fails to manifest itself or manifests differently during debugging.
What part of speech is heisenbug?
Heisenbug is a noun.
How do you pronounce heisenbug?
Heisenbug is pronounced /ˈhaɪzənˌbʌɡ/.
What is the plural of heisenbug?
The plural of heisenbug is heisenbugs.

Words near heisenbug in the dictionary

  1. Heisenberg principle
  2. Heisenberg uncertainty principle
  3. Heisenberg's principle
  4. Heisenbergian
  5. Heisenbergians
  6. heisenbug
  7. heisenbugs
  8. Heiser
  9. Heiserman
  10. Heisermans
  11. Heisers

Source and license

Adapted from Wiktionary: heisenbug (page history and authors); Heisenbug (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Pronunciation audio from Wikimedia Commons, each file under its own free license: en-uk-heisenbug.ogg.

Cite this entry: “heisenbug.” Word.ws, https://word.ws/heisenbug. Based on Wiktionary, CC BY-SA 4.0.