/en vuy"reuhn, -vuy"euhrn/ , v.t.
to form a circle or ring round; surround; envelop: a house environed by pleasant grounds; to be environed by bad influences.
[ 1300-50; ME envirounen environner, deriv. of environ around ( en EN- 1 + viron a circle; vir ( er ) to turn, VEER + -on n. suffix) ]