What does "exterior" mean?

Exterior: External; on the outside; without the limits of; extrinsic; as, an object exterior to a man, opposed to what is within, or in his mind. Without exterior help sustained. Milton.

Additional senses

  1. 2.Relating to foreign nations; foreign; as, the exterior relations of a state or kingdom. Exterior angle (Geom.), the angle included between any side of a triangle or polygon and the prolongation of the adjacent side; also, an angle included between a line crossing two parallel lines and either of the latter on the outside. -- Exterior side (Fort.), the side of the polygon upon which a front of fortification is formed. Wilhelm. Note: See Illust. of Ravelin.
  2. 3.The outward surface or part of a thing; that which is external; outside.
  3. 4.Outward or external deportment, form, or ceremony; visible act; as, the exteriors of religion.

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