to encircle or surround completely; to enclose within bounds.
From 'be-' plus 'compass' (meaning to circle or enclose). The noun 'compass' originally meant a circular boundary, making this verb mean 'to surround in a circle.'
'Compass' originally meant 'to go around'—it's why a magnetic compass helps you go around the world and why 'encompass' means 'to contain'—becompass is an older variant of this 'encircling' meaning.
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