Meanings
- alternativenot comparableAlternative form of falsy.
If the variable is set to anything except a falsey value, the test will evaluate to true.
2010, Charles Wyke-Smith, Scriptin' with JavaScript and Ajax: A Designer's Guide, →ISBN, page 443 more examples
In JavaScript, as well as the true or false Boolean values, other types of variables can be said to be truthy or falsey.
2013, Dan Wellman, jQuery Hotshot, →ISBNTo remember which values are truthy and which are falsey, just memorize the five falsey values - undefined, null, 0, "" and NaN -- and remember that everything else is truthy.
2014, Eric T. Freeman, Elisabeth Robson, Head First JavaScript Programming: A Brain-Friendly Guide, →ISBN, page 292Clojure uses the Boolean operators or and and. or returns either the first truthy value or the last value, and returns the first falsey value or, if no values are falsey, the last truthy value.
2015, Daniel Higginbotham, Clojure for the Brave and True, →ISBN, page 40
Rhymes & wordplay
Anagrams
Cite this entry
falsey. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/falsey
“falsey.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/falsey. Accessed November 3, 2026.
WatkinsX Dictionary, s.v. “falsey,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/falsey.
Source: falsey on Wiktionary, CC BY-SA 4.0.