father-in-law

noun

ˈfä-t͟hə-rən-ˌlȯ 

-t͟hərn-ˌlȯ

plural fathers-in-law ˈfä-t͟hər-zən-ˌlȯ 

1

: the father of one's spouse

2

archaic : stepfather

Examples of father-in-law in a Sentence

Recent Examples on the Web

In prosecutors’ telling, Ryan, fueled by his anger, intentionally killed his father-in-law, who was remembered by several friends as a principled and loving family man. —Mark Morales, CNN Money, 14 May 2026

Back in London, father-in-law King Charles III, who is also undergoing cancer treatment, was carrying out one of the monarchy's grandest ceremonial duties on Wednesday, delivering a landmark speech for the formal opening of a new session of the British Parliament. —Elena Giuliano, CBS News, 13 May 2026

Kate first went public with her cancer diagnosis in March 2024, a month after King Charles III, her father-in-law, announced his own cancer diagnosis publicly. —ABC News, 13 May 2026

Inside the locket, according to Brett, are pictures of her mother-in-law and father-in-law. —Abigail Adams, PEOPLE, 12 May 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1

Rhymes for father-in-law

• avoirdupois
• aa
• aha
• bashaw
• bradshaw
• byelaw
• bylaw
• chainsaw
• cheraw
• coleslaw
• crenshaw
• dada

Kids Definition

father-in-law

noun

fa·​ther-in-law

ˈfät͟h-(ə-)rən-ˌlȯ, 

ˈfȧt͟h-, 

-ərn-ˌlȯ

plural fathers-in-law

ˈfät͟h-ər-zən-, 

ˈfȧt͟h-

: the father of one's husband or wife