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Webster 1913 Edition
Perpendicularly
Perˊpen-dic′u-lar-ly
,adv.
In a perpendicular manner; vertically.
Webster 1828 Edition
Perpendicularly
PERPENDIC'ULARLY
,adv.
1.
So as to fall on the plane of the horizon at right angles; in a direction towards the center of the earth or of gravity.