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

After his unsuccessful challenge regarding his compensation, Gregoire said he went to Dominica to live with his grandfather in his wooden house for six months.

From BBC • May 27, 2026

The judge accepted that Crowley had inherited the statues from his grandfather and did not at any point believe that they were counterfeits.

From BBC • May 22, 2026

After my grandfather was buried in Hollywood Forever Cemetery in 2009, I have watched the little path that leads to his tombstone go from a muddy dirt trail to neatly paved with bricks.

From Los Angeles Times • May 19, 2026

After pausing distilling operations in Clermont, the company moved most of its production to its Booker Noe facility just down the street, named for Noe’s grandfather.

From The Wall Street Journal • May 17, 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