ABOUND (v.)
“be in great plenty” (14c.), from Old French abonder “to abound, be abundant, come together in great numbers” (12c.), from Latin abundare “overflow, run over,” from Latin ab “off, away from” + undare “rise in a wave,” from unda “a wave,” from √WED- “water; wet”
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SURROUND(v.)
“to flood, overflow” (15c.), from Middle French soronder “to overflow, abound; surpass, dominate,” from Late Latin superundare “overflow,” from Latin super “over” + undare “to flow in waves.” Sense of “to shut in on all sides” (1610s) influenced by figurative meaning in French of “dominate,” and by sound association with round