surge (n.)

late 15c. (Caxton), "fountain, spring of water" (a sense now obsolete), a word of uncertain origin, probably from French sourge-, stem of sourdre "to rise, swell," from Latin surgere "to rise, arise, get up, mount up, ascend; attack," contraction of surrigere, from assimilated form of sub "up from below" (see sub-) + regere "to keep straight, guide" (from PIE root *reg- "move in a straight line," with derivatives meaning "to direct in a straight line," thus "to lead, rule").

The meaning "high, rolling swell of water, large wave or billow" is from 1520s; figurative sense of "an excited rising up" (as of feelings) is from 1510s. As "act of surging," by 1660s.

1510s, "to rise and fall" on or as on the waves, a sense now obsolete, from surge (n.), or from French surgir "rise, ride (as a ship does a wave), spring up, arrive." The meaning "rise in waves, rise high and roll forcefully" is from 1560s, literal and figurative. Related: Surged; surging.