grandfather

American  

[gran-fah-ther, grand-] / ˈgrænˌfɑ ðər, ˈgrænd- /

noun

grandfathers plural

1. the father of one's father or mother.

2. a forefather.

3. the founder or originator of a family, species, type, etc.; the first of one's or its kind, or the one being longest in existence.

   the grandfather of all steam locomotives.

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verb (used with object)

1. to exempt (something or someone) from new legislation, restrictions, or requirements.

   The law grandfathered all banks already operating at the time of passage. He was grandfathered into the pension plan.

grandfather British  

/ ˈɡrænd-, ˈɡrænˌfɑːðə /

noun

1. the father of one's father or mother

2. (often plural) a male ancestor

3. (often capital) a familiar term of address for an old man

4. dialect a caterpillar or woodlouse

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Other Word Forms

Noun Inflected Forms

• grandfathers
  plural

Etymology

Origin of grandfather

late Middle English word dating back to 1375–1425; see origin at grand-, father

Explanation

Your grandfather is the father of one of your parents. If your grandfather is quite old and has dozens of grandchildren, it might be hard for him to remember your birthday every year. Everyone has two biological grandfathers, whether they've had the chance to know them or not. In some families, grandmothers and grandfathers are involved in raising and caring for their grandchildren, while in others a grandfather may have died or live very far away. Informally, a grandfather can also be someone who started or invented something: "Blues musician Robert Johnson was the grandfather of rock and roll."

Example Sentences

They playfully refer to this new cut that audiences will see globally as “The Grandfather Cut,” to honor Del Toro’s influence.

From Los Angeles Times • Jun. 15, 2026

Drawing on facts and clues that Kaede learns from the news and her own snooping, Grandfather ponders solutions in the sanctuary of his library.

From The Wall Street Journal • Mar. 27, 2026

"I'm disappointed in this whole chamber right now," the self-described "Christian, Husband, Father, Grandfather" said as he presented a group of high school basketball champions.

From Salon • Mar. 20, 2024

“His Grandfather is on the Chumash Tribe board up in Santa Ynez,” said the page.

From Washington Times • Nov. 29, 2023

I remembered Grandfather Burke sliding his bowl over to me and saying, “That’s for you, doodlebug. Take what is offered to you.”

From "Louisiana's Way Home" by Kate DiCamillo

Related Words

• ancestor
• grandpa
• patriarch