eddy (n.)
mid-15c., Scottish ydy, possibly from Old Norse iða "whirlpool," from Proto-Germanic *ith- "a second time, again," which is related to the common Old English prefix ed- "again, backwards; repetition, turning" (forming such words as edðingung "reconciliation," edgift "restitution," edniwian "to renew, restore," edhwierfan "to retrace one's steps," edgeong "to become young again"). Compare Old English edwielle "eddy, vortex, whirlpool." The prefix is cognate with Latin et, Old High German et-, Gothic "and, but, however." Related: Eddies.
eddy (v.)
1810, from eddy (n.). Related: Eddied; eddying.