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.
Phrases and idioms:
surge chamber (or tank) a chamber designed to neutralize sudden changes of pressure in a flow of liquid.
Etymology: OF sourdre sourge-, or sorgir f. Cat., f. L surgere rise