grandfather

American  

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

noun

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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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

To fight these “little scarlet cells,” Grandfather seeks inspiration in the “little gray cells” of Hercule Poirot.

From The Wall Street Journal • Mar. 27, 2026

Grandfather Mr O'Halloran was originally from County Clare in western Ireland and had been well known in the local community.

From BBC • Apr. 29, 2024

"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

Little Willy loved to look at all the people, especially the “city slickers,” as Grandfather called them.

From "Stone Fox" by John Reynolds Gardiner

Related Words

• ancestor
• grandpa
• patriarch