The Collaborative International Dictionary of English v.0.48:

Son \Son\, n. [OE. sone, sune, AS. sunu; akin to D. zoon, OS.,
   OFries., & OHG. sunu, G. sohn, Icel. sonr, Sw. son, Dan.
   s["o]n, Goth. sunus, Lith. sunus, Russ. suin', Skr. s[=u]nu
   (from s[=u] to beget, to bear), and Gr. ? son. [root]293. Cf.
   Sow, n.]
   1. A male child; the male issue, or offspring, of a parent,
      father or mother.
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            Sarah conceived, and bare Abraham a son. --Gen. xxi.
                                                  2.
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   2. A male descendant, however distant; hence, in the plural,
      descendants in general.
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            I am the son of the wise, the son of ancient kings.
                                                  --Isa. xix.
                                                  11.
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            I am the Lord, I change not; therefore ye sons of
            Jacob are not consumed.               --Mal. iii. 6.
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   3. Any young male person spoken of as a child; an adopted
      male child; a pupil, ward, or any other young male
      dependent.
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            The child grew, and she brought him unto Pharaoh's
            daughter, and he became her son.      --Ex. ii. 10.
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            Be plain, good son, and homely in thy drift. --Shak.
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   4. A native or inhabitant of some specified place; as, sons
      of Albion; sons of New England.
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   5. The produce of anything.
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            Earth's tall sons, the cedar, oak, and pine.
                                                  --Blackmore.
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   6. (Commonly with the def. article) Jesus Christ, the Savior;
      -- called the Son of God, and the Son of man.
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            We . . . do testify that the Father sent the Son to
            be the Savior of the world.           --1 John iv.
                                                  14.
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            Who gave His Son sure all has given.  --Keble.
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   Note: The expressions son of pride, sons of light, son of
         Belial, are Hebraisms, which denote persons possessing
         the qualitites of pride, of light, or of Belial, as
         children inherit the qualities of their ancestors.
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   Sons of the prophets. See School of the prophets, under
      Prophet.
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WordNet (r) 3.0 (2006):

son
    n 1: a male human offspring; "their son became a famous judge";
         "his boy is taller than he is" [syn: son, boy] [ant:
         daughter, girl]
    2: the divine word of God; the second person in the Trinity
       (incarnate in Jesus) [syn: Son, Word, Logos]

Moby Thesaurus II by Grady Ward, 1.0:

62 Moby Thesaurus words for "son":
   aunt, auntie, blood brother, brethren, brother, bub, bubba, bud,
   buddy, child, country cousin, cousin, cousin once removed,
   cousin twice removed, daughter, descendant, father, first cousin,
   foster brother, foster child, frater, grandchild, granddaughter,
   grandnephew, grandniece, grandson, granduncle, great-aunt,
   great-uncle, half brother, heiress, junior, kid brother, lad,
   laddie, mother, nephew, niece, nuncle, nunks, nunky, offspring,
   scion, second cousin, sis, sissy, sister, sister-german, sistern,
   son and heir, sonny, stepbrother, stepchild, stepdaughter,
   stepsister, stepson, stripling, tad, unc, uncle, uncs,
   uterine brother



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

SON, kindred. An immediate male descendant. In its technical meaning in
devises, this is a word of purchase, but the testator may make it a word of
descent. Sometimes it is extended to more remote descendants.