father-in-law
Americannoun
plural
fathers-in-lawnoun
Etymology
Origin of father-in-law
First recorded in 1350–1400; Middle English fader in lawe; see origin at father, in, law 1; from Middle English in-lawe “in law,” i.e., “a person within the regulation and protection of the law,” based on the prohibition by Roman civil law and, later, Christian canon law, of marriages within four degrees of consanguinity, i.e., up to and including first cousins
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Dean Buntrock was happily selling life insurance in Boulder, Colo., in 1956 when the death of his father-in-law thrust him into a very different business: hauling garbage in Chicago.
From The Wall Street Journal • Apr. 28, 2026
Some of the building's residents are "still homeless", as well as Haycock's 87- year-old father-in-law, who has terminal cancer.
From BBC • Mar. 13, 2026
Warsh’s father-in-law is Ron Lauder, a longtime friend of Trump’s.
From Barron's • Jan. 30, 2026
Warsh’s father-in-law, Ronald Lauder, is a former classmate of Trump’s and a major Republican donor.
From The Wall Street Journal • Jan. 30, 2026
The voting was absolutely free, as Aureliano himself was able to attest since he spent almost the entire day with his father-in-law seeing that no one voted more than once.
From "One Hundred Years of Solitude" by Gabriel Garcia Marquez
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
