The definition of niece is the daughter of your brother or sister, by blood or by marriage.(noun)
An example of a niece is your brother-in-law's daughter.
See niece in Webster's New World College Dictionary
Origin: ME nece < OFr niece < LL neptia < L neptis, granddaughter, niece, akin to nepos, nephew
See niece in American Heritage Dictionary 4
Origin: Middle English nece
Origin: , from Old French
Origin: , from Vulgar Latin *neptia
Origin: , from Latin neptis; see nepōt- in Indo-European roots.
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