con-vallo

āvi, ātum, 1
I. v. a.; lit., to surround with an intrenchment; hence, in gen., to surround, encircle (late Lat.): terras omnes Oceani ambitu, Gell. 12, 13, 20. —Trop., Tert. Carm. de Judicio Dom. 6.
Lewis & Short
A Latin Dictionary, 1879
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