Meanings
alternative falsey
- not comparablecomputingEvaluating to false in a Boolean context.
However, in the second case, both '0' and the empty string () are falsy (in other words, they behave like false) and are therefore equal with respect to ==.
2014, Basarat Syed, Beginning Node.js, →ISBN, page 332 more examples
In JavaScript, any expression or statement that expects a boolean value will work with a truthy or falsy value, so the fact that && does not always evaluate to true or false does not cause practical problems.
2012, David Flanagan, JavaScript Pocket Reference, page 40If the first operand (which comes before the question mark--doIt, in this example) is truthy, the expression evaluates to the second operand (between the question mark and colon), and if it's falsy, it evaluates to the third operand (after the colon).
2016, Kenny Ballou, Learning Elixir, →ISBN, page 92Antonyms: truthy
Synonyms & antonyms
adjectiveEvaluating to false in a Boolean context.
Origin
From false + -y, to be an antonym to truthy.
Full word history & related roots →Rhymes & wordplay
Sounds the same
Cite this entry
falsy. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/falsy
“falsy.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/falsy. Accessed November 3, 2026.
WatkinsX Dictionary, s.v. “falsy,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/falsy.
Source: falsy on Wiktionary, CC BY-SA 4.0.