n. & v.
n. 1 a sudden or impetuous onset (a surge of anger). 2 the swell of the waves at sea. 3 a heavy forward or upward motion. 4 a rapid increase in price, activity, etc. over a short period. 5 a sudden marked increase in voltage of an electric current.
v.intr. 1 (of waves, the sea, etc.) rise and fall or move heavily forward. 2 (of a crowd etc.) move suddenly and powerfully forwards in large numbers. 3 (of an electric current etc.) increase suddenly. 4 Naut. (of a rope, chain, or windlass) slip back with a jerk. surge chamber (or tank) a chamber designed to neutralize sudden changes of pressure in a flow of liquid.
[ OF sourdre sourge-, or sorgir f. Cat., f. L surgere rise ]