Aberration

(ab-er-ra's hun.) [From Lat. aberro, I wander away.] (Opt.) An unequal deviation of rays of light when refracted by a lens, or reflected from a concave mirror; in consequence of which they are prevented from meeting in the same point. A. are of two kinds: one arising from the figure of the reflecting or refracting body; the other from the unequal refrangibility of the different colored rays which, united together, constitute white light, and which, being sep a a rated by the lens, give rise to the production of colors. - (Astron.) An apparent displacement of a celestial object, due to the progre ive motion of light. A. is caused in two ways: first, by the orbital motion of the earth, and, secondly, by the motion of the observed celestial bodies. [s. 3]