The parent of one's mother or father; a grandmother or grandfather.
The 'grand' in grandparent doesn't mean 'wonderful' as many assume, but comes from French 'grand' meaning 'great' or 'large' in the sense of generation distance. It literally means 'great parent' - one generation removed. The term emerged in English around 1300, when French influence was strong after the Norman Conquest. Before this, English speakers used terms like 'eldmother' and 'eldfather.'
Every time you say 'grandparent,' you're speaking medieval French! The word preserves a time when English aristocrats spoke French at court while common people spoke Old English. It's why we have both 'grandfather' (French-influenced) and the older Germanic 'grandsire' in English, showing the linguistic class divide of medieval England.
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