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

raca \ra"ca\ r=a"k.a, a. gr. "raka`, from chaldee
   r=ek=a.
   a term of reproach used by the jews of our savior's time,
   meaning "worthless."
   1913 webster

         whosoever shall say to his brother, raca, shall be in
         danger of the council.                   --matt. v. 22.
   1913 webster

[2] : Easton's 1897 Bible Dictionary

raca
   vain, empty, worthless, only found in matt. 5:22. the jews used
   it as a word of contempt. it is derived from a root meaning "to
   spit."
   

[3] : Hitchcock's Bible Names Dictionary (late 1800's)

raca, worthless; good-for-nothing

Raca >> R Words
Raca, definition of term: Raca
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