What does "against" mean?

Against: From an opposite direction so as to strike or come in contact with; in contact with; upon; as, hail beats against the roof.

Additional senses

  1. 2.In opposition to, whether the opposition is of sentiment or of action; on the other side; counter to; in contrariety to; hence, adverse to; as, against reason; against law; to run a race against time. The gate would have been shut against her. Fielding. An argument against the use of steam. Tyndale.
  2. 3.By of before the time that; in preparation for; so as to be ready for the time when. [Archaic or Dial.] Urijah the priest made it, against King Ahaz came from Damascus. 2 Kings xvi.
  3. 4.Against the sun, in a direction contrary to that in which the sun appears to move.

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