Origin: 1400–50;late Middle Englishsurounden to inundate, submerge < Anglo-Frenchsurounder,Middle Frenchs(o)ronder < Late Latinsuperundāre to overflow, equivalent to Latinsuper-super- + undāre to flood, derivative of unda wave (see undulate); current spelling by analysis as sur-1 + round1 (v.)
1423, "to flood, overflow," from M.Fr. soronder "to overflow, abound, surpass, dominate," from L.L. superundare "overflow," from L. super "over" (see super-) + undare "to flow in waves," from unda "wave" (see water; and cf.
abound). Sense of "to shut in on all sides" first recorded 1616, influenced by figurative meaning in Fr. of "dominate," and by sound association with round. First record of surroundings in sense of "environment" is from 1861.