Grandfather vs Popsy - What's the difference?

grandfather | popsy |

As nouns the difference between grandfather and popsy

is that grandfather is a father of someone’s parent while popsy is (informal) grandfather or popsy can be (uk|slang|dated) a girl.

As a verb grandfather

is to retain existing laws or rules only for those people or organisations that were previously affected by them, and apply new laws or rules to the unaffected people or organizations.