Word.ws English Dictionary

knuckleball

knuckleball noun: a pitch thrown with the ball gripped on the fingertips and released with no rotation, which travels over an unpredictable path to the plate due to microturbulence in the air.

Noun

knuckleball (plural knuckleballs)

  1. A pitch thrown with the ball gripped on the fingertips and released with no rotation, which travels over an unpredictable path to the plate due to microturbulence in the air.
    • Even the pitcher doesn't know where his knuckleball is going.
    • Boston Red Sox pitcher Tim Wakefield is best known for his use of the knuckleball.
    Synonyms:
    flutterball, floater, dancer, butterfly ball, ghostball, bug
  2. A type of delivery where a fast bowler holds the ball on the knuckles of the index and middle fingers.
  3. (figuratively, informal) An event that is hard to predict.
    • Our vendor keeps throwing us knuckleballs.

Verb

knuckleball (third-person singular simple present knuckleballs, present participle knuckleballing, simple past and past participle knuckleballed)

  1. (intransitive) To pitch knuckleballs.
    • Varitek did not start so Kevin Cash could catch the knuckleballing starter Tim Wakefield.2008 April 16, The Associated Press, “Tigers Rally Again to Defeat the Twins”, in New York Times

Synonyms of knuckleball

All synonyms of knuckleball

Forms of knuckleball

Noun
pluralknuckleballs
Verb
third-person singular presentknuckleballs
present participleknuckleballing
past participleknuckleballed
pastknuckleballed

Origin of knuckleball

From knuckle + ball.

Words formed from knuckleball

Questions about knuckleball

What does knuckleball mean?
Knuckleball means a pitch thrown with the ball gripped on the fingertips and released with no rotation, which travels over an unpredictable path to the plate due to microturbulence in the air.
What part of speech is knuckleball?
Knuckleball can be a noun or a verb.
What is the plural of knuckleball?
The plural of knuckleball is knuckleballs.

Words near knuckleball in the dictionary

  1. knuckle-scraper
  2. knuckle-scrapers
  3. knuckle-tat
  4. knuckle-tats
  5. knuckle-walking
  6. knuckleball
  7. knuckleballed
  8. knuckleballer
  9. knuckleballers
  10. knuckleballing
  11. knuckleballs

Source and license

Adapted from Wiktionary: knuckleball (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.

Last updated:

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