The plural of niece, which is the daughter of your sibling or your sibling's child.
From Old French 'nice,' from Latin 'neptis' (granddaughter, descendant). The term passed through French to become 'niece' and applied specifically to a sister's or brother's daughter.
The Latin 'neptis' originally meant any female descendant, but as families became more nuclear and terminology more specific, it narrowed down to just mean your sibling's daughter—language follows social change.
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