ivyeight6 wrote:
Do you have any reasons?
Question is excessively vague.
Anyway, here's some word history from Online Etymology, maybe that's what you are wanting, but there's no reason you couldn't have looked this up yourself;
Quote:
nephew (n.)
c. 1300, neveu, "son of one's sister or brother," also "a grandson; a relative; a kinsman," from Old French neveu (Old North French nevu) "grandson, descendant," from Latin nepotem (nominative nepos) "sister's son, grandson, descendant," in post-Augustan Latin (c. 150 A.D.), "nephew," from PIE *nepot- "grandchild," and in a general sense, "male descendant other than son" (source also of Sanskrit napat "grandson, descendant;" Old Persian napat- "grandson;" Old Lithuanian nepuotis "grandson;" Dutch neef; German Neffe "nephew;" Old Irish nia, genitive niath "son of a sister," Welsh nei).
The original pronunciation is /nev-u/; the spelling was changed unetymologically to -ph- after c. 1400, and the pronunciation partly followed it. Used in English in all the classical senses until the meaning narrowed in 17c.
Quote:
niece (n.)
c. 1300, nece, "daughter of one's brother or sister; granddaughter; female relative," from Old French niece "niece; granddaughter" (12c., Modern French nièce), earlier niepce, from Latin neptia (also source of Portuguese neta, Spanish nieta), a more decidedly feminine form of neptis "granddaughter," in Late Latin "niece," fem. of nepos "grandson, nephew" (see nephew). Cognate with Old Lithuanian neptė, Sanskrit naptih "granddaughter;" Czech net, Old Irish necht, Welsh nith, German Nichte "niece."
It replaced Old English nift, from Proto-Germanic *neftiz, from the same PIE root (Old English also used broðordohter and nefene). Until c. 1600 in English, niece also commonly meant "a granddaughter" or any remote female descendant or kinswoman.
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