noun
grandfather
GRAN-fah-thuh
noun
1
The father of one's mother or father.
"Her grandfather fought in the war as a young man."
verb
1
To exempt someone or something from a new rule because they were already operating under the old one.
"Existing tenants were grandfathered in under the old rent rules."
How to Use Grandfather
Learner’s notesIn plain EnglishAs a noun, your parent's father; as a verb, to let something old avoid a new rule.
Memory tip
The verb use ("grandfathered in") is common in law, business, and software — it means the old version keeps its old privileges.
Trace the full origin ↓
Common pairings
grandfather clock
grandfathered in
great-grandfather
Word Forms
grandfathered past tense, grandfathered past tense, grandfathers plural, grandfathers singular, grandfathers singular
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Her _____ fought in the war as a young man.
Etymology
From Middle English grandfadre, modeled on French grand-père, replacing the older English "eldfather."