What is "aspect of a plane"

Aspect \As"pect\, n. [L. aspectus, fr. aspicere, aspectum, to look at; ad + spicere, specere, to look, akin to E. spy.]

1. The act of looking; vision; gaze; glance. [R.] ``The basilisk killeth by aspect.''
   --Bacon.

   His aspect was bent on the ground.
   --Sir W. Scott.

2. Look, or particular appearance of the face; countenance; mien; air. ``Serious in aspect.''
   --Dryden.

   [Craggs] with aspect open shall erect his head.
   --Pope.

3. Appearance to the eye or the mind; look; view. ``The aspect of affairs.''
   --Macaulay.

   The true aspect of a world lying in its rubbish.
   --T. Burnet.

4. Position or situation with regard to seeing; that position which enables one to look in a particular direction; position in relation to the points of the compass; as, a house has a southern aspect, that is, a position which faces the south.

5. Prospect; outlook. [Obs.]

   This town affords a good aspect toward the hill from whence we descended.
   --Evelyn.

6. (Astrol.) The situation of planets or stars with respect to one another, or the angle formed by the rays of light proceeding from them and meeting at the eye; the joint look of planets or stars upon each other or upon the earth.
   --Milton.

   Note: The aspects which two planets can assume are five; sextile, ?, when the planets are 60[deg] apart; quartile, or quadrate, ?, when their distance is 90[deg] or the quarter of a circle; trine, ?, when the distance is 120[deg]; opposition, ?, when the distance is 180[deg], or half a circle; and conjunction, ?, when they are in the same degree. Astrology taught that the aspects of the planets exerted an influence on human affairs, in some situations for good and in others for evil.

7. (Astrol.) The influence of the stars for good or evil; as, an ill aspect.
   --Shak.

   The astrologers call the evil influences of the stars evil aspects.
   --Bacon.

8. (A["e]ronautics) A view of a plane from a given direction, usually from above; more exactly, the manner of presentation of a plane to a fluid through which it is moving or to a current. If an immersed plane meets a current of fluid long side foremost, or in broadside aspect, it sustains more pressure than when placed short side foremost. Hence, long narrow wings are more effective than short broad ones of the same area.

   Aspect of a plane (Geom.), the direction of the plane.