WordNet (r) 3.0 (2006):

Reuben
    n 1: (Old Testment) a son of Jacob and forefather of one of the
         tribes of Israel
    2: a hot sandwich with corned beef and Swiss cheese and
       sauerkraut on rye bread

Easton's 1897 Bible Dictionary:

Reuben
   behold a son!, the eldest son of Jacob and Leah (Gen. 29:32).
   His sinful conduct, referred to in Gen. 35:22, brought down upon
   him his dying father's malediction (48:4). He showed kindness to
   Joseph, and was the means of saving his life when his other
   brothers would have put him to death (37:21,22). It was he also
   who pledged his life and the life of his sons when Jacob was
   unwilling to let Benjamin go down into Egypt. After Jacob and
   his family went down into Egypt (46:8) no further mention is
   made of Reuben beyond what is recorded in ch. 49:3,4.


Hitchcock's Bible Names Dictionary (late 1800's):

Reuben, who sees the son; the vision of the son