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Related to grandfather: Grandfather paradox

(a) grandfather clause

a clause in an agreement that protects certain rights granted in the past even when conditions change in the future. The contract contained a grandfather clause that protected my pension payments against claims such as might arise from a future lawsuit.
See also: grandfather

grandfather someone or something in

to protect someone or a right through the use of a grandfather clause. My payments were grandfathered in years ago.
See also: grandfather
References in classic literature ?
Nor will it become me to resent any rudeness towards either my grandfather or myself.
Were I to do so, my grandfather would not rest quiet in his grave
On the contrary, after seven-and-thirty years, the presence of his dead grandfather seemed still to pervade it, as on that morning when the affrighted boy had beheld him, with so ghastly an aspect, stiffening in his chair.
Pyncheon set down the emptied glass, he thought be beheld his grandfather frown.
I do not wish it," said the eye of her grandfather.
Valentine was looking at her grandfather with a smile of intense gratitude, and Villefort was biting his lips with vexation, while Madame de Villefort could not succeed in repressing an inward feeling of joy, which, in spite of herself, appeared in her whole countenance.
Well, child," said Grandfather, patting Clara's cheek, "I can tell you a great many stories of my chair.
Meantime, little Alice was already asleep; so Grandfather, being much pleased with such an attentive audience, began to talk about matters that happened long ago.
George makes the latter remark to himself as he nods to Grandfather Smallweed.
he asks of Grandfather Smallweed after looking round the room.
cries Grandfather Smallweed, stretching out both hands to embrace him.
He dressed for dinner every day, "like a regular West End swell," as his grandfather remarked; one of the domestics was affected to his special service, attended him at his toilette, answered his bell, and brought him his letters always on a silver tray.
The wealth of his grandfather was reported in the school to be prodigious.
As for the learning which Georgy imbibed under this valuable master of a hundred sciences, to judge from the weekly reports which the lad took home to his grandfather, his progress was remarkable.
She left her grandfather in his chamber, and followed her guide to another, which was at the end of a passage, and approached by some half-dozen crazy steps.