Webster's Revised Unabridged Dictionary · 1913

Raca

Raca (rā"kȧ) , adjective

[Greek "raka`, from Chaldee rēkā.]

A term of reproach used by the Jews of our Savior's time, meaning “worthless.”
Whosoever shall say to his brother, Raca, shall be in danger of the council. — Matt. v. 22