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

Harry and Meghan have lived in California since 2020 and the children had not seen their grandfather since 2022.

From Barron's • Jul. 10, 2026

Her mother was a teacher before she married Charles Ingalls; her maternal grandfather died from drowning.

From Los Angeles Times • Jul. 9, 2026

He retired from politics in 2009 and today, at 89, lives in Vrana Palace, the royal estate his grandfather built.

From The Wall Street Journal • Jul. 6, 2026

My love for the Fourth comes from my grandfather, who emigrated to this country from Lebanon.

From Salon • Jul. 3, 2026

Jack’s grandfather asked him, puffing on a new pipe made of solid gold.

From "Half Upon a Time" by James Riley

Related Words

• ancestor
• grandpa
• patriarch