[1] : The Collaborative International Dictionary of English v.0.48

nephew \neph"ew\ ne^f"-u; in england ne^v"-u; 277, n.
   oe. neveu, nevou, nevu, fr. f. neveu, of. also, nevou, l.
   nepos; akin to as. nefa, d. neef, g. neffe, ohg. nevo, icel.
   nefi a kinsman, gr. ne`podes, pl., brood, young, skr.
   nep=at grandson, descendant. root262. cf. niece,
   nepotism.
   1. a grandson or grandchild, or remoter lineal descendant.
      obs.
      1913 webster

            but if any widow have children or nephews rev. ver.
            grandchildren.                     --1 tim. v. 4.
      1913 webster

            if naturalists say true that nephews are often liker
            to their grandfathers than to their fathers. --jer.
                                                  taylor.
      1913 webster

   2. a cousin. obs. --shak.
      1913 webster

   3. the son of a brother or a sister, or of a brother-in-law
      or sister-in-law. --chaucer.
      1913 webster
see also:
niece nepotism grandchildren 

[2] : WordNet (r) 2.0

nephew
     n : a son of your brother or sister ant: niece
see also:
niece 

[3] : Moby Thesaurus II by Grady Ward, 1.0

43 moby thesaurus words for "nephew":
   aunt, auntie, blood brother, brethren, brother, bub, bubba, bud,
   buddy, country cousin, cousin, cousin once removed,
   cousin twice removed, daughter, father, first cousin,
   foster brother, frater, grandnephew, grandniece, granduncle,
   great-aunt, great-uncle, half brother, kid brother, mother, niece,
   nuncle, nunks, nunky, second cousin, sis, sissy, sister,
   sister-german, sistern, son, stepbrother, stepsister, unc, uncle,
   uncs, uterine brother

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

nephew, dom. rel. the son of a person's brother or sister. amb. 514; 1 
jacob's ch. r. 207. 

Nephew >> N Words
Nephew, definition of term: Nephew
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