as the day is long(redirected from deceitful)
Also found in: Dictionary, Thesaurus, Legal, Encyclopedia, Wikipedia.
as the day is long
Absolutely; to the utmost degree; as much as is possible. Used as an intensifier of an adjective. Ever since she proposed to me, I've been as happy as the day is long. Don't trust a word he says—he's as deceitful as the day is long. Our company is looking for talented individuals who are loyal as the day is long.
See also: long
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.