An Etymological Dictionary of Astronomy and Astrophysics

1. Opposite in nature or character; diametrically or mutually opposed.
   

   2. Opposite in direction or position (Dictionary.com).

Etymology (EN): From Anglo-French contrarie, O.Fr. contrarie, and directly from L. contrarius “opposite, opposed; contrary, reverse,” from contra “against”

Etymology (PE): Pârun, → opposite.