Word.ws English Dictionary

headcase

headcase noun: a mentally unbalanced, unpredictable person, especially one who displays aggressive behavior.

Noun

headcase (countable and uncountable, plural headcases)

  1. (countable, derogatory, informal) A mentally unbalanced, unpredictable person, especially one who displays aggressive behavior.
    • "A stockbroker doesn't have 80,000 people sitting behind him just waiting for a mistake," says Jim Fassel, whom fans serenaded with "Fire Fassel!" chants during his final weeks as head coach of the New York Giants last season. "It can drive you crazy." From head coach to head case in three easy...2004 April 5, Sean Gregory, “Full-Court Stress”, in Time, archived from the original on 28 Oct 2010
  2. (uncountable) A genetic sequence that inhibits terminal branching of the trachea and regulates dendrite pruning.
    • Another gene downstream of EcR/Usp is headcase. Screening genes that show genetic interactions with EcR mutants, Loncle and Williams identified headcase as a regulator of dendrite pruning (Loncle and Williams 2012).2016, Kazuo Emoto, Rachel Wong, Eric Huang, Casper Hoogenraad, editors, Dendrites: Development and Disease, Springer, →ISBN, page 280
    Synonyms:
    hdc

Synonyms of headcase

Forms of headcase

pluralheadcases
alternative formhead-case
alternative formhead case

Origin of headcase

From head + case.

Questions about headcase

What does headcase mean?
Headcase means a mentally unbalanced, unpredictable person, especially one who displays aggressive behavior.
What part of speech is headcase?
Headcase is a noun.
What is the plural of headcase?
The plural of headcase is headcases.

Words near headcase in the dictionary

  1. headcap
  2. headcapped
  3. headcaps
  4. headcarries
  5. headcarry
  6. headcase
  7. headcases
  8. headcast
  9. headcasts
  10. headchair
  11. headchairs

Source and license

Adapted from Wiktionary: headcase (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: LL-Q1860 (eng)-Flame, not lame-headcase.wav.

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