Offence - (Easton's Bible Dictionary)
(1.) An injury or wrong done to one (1 Sam. 25:31; Rom. 5:15).
(2.) A stumbling-block or cause of temptation (Isa. 8:14; Matt. 16:23; 18:7). Greek skandalon, properly that at which one stumbles or takes offence. The "offence of the cross" (Gal. 5:11) is the offence the Jews took at the teaching that salvation was by the crucified One, and by him alone. Salvation by the cross was a stumbling-block to their national pride.