Meaning of GRANDFATHER in English

I. ˈgran(d)ˌ ̷ ̷ ̷ ̷, -raan- noun

Etymology: Middle English graund fader (translation of Middle French grant pere ), from Middle French grant grand + Middle English fader father — more at grand , father

1. : a father's or mother's father : an ancestor in the next degree above the father or mother in lineal ascent ; also : forefather

2. : one suggesting a grandfather in being a precursor in a line of similar things showing successive development, in being old and venerable, or in being the first or earliest in a line

the church supper is the grandfather of the country club — Saturday Review

an old grandfather of a tree

also : something sizable or impressive in a way suggesting a long period of growth or development

the grandfather of all buttons — Ben Riker

II. transitive verb

: to permit to continue under a grandfather clause

existing personnel would be grandfathered into the present system — Wall Street Journal

grandfathered water rights

Webster's New International English Dictionary.      Новый международный словарь английского языка Webster.