ortho-

  1. Prefix.  straight, right, proper.
  2. Prefix.  (chemistry) Having an extra proportion of water.
  3. Prefix.  (chemistry) in isomeric benzene derivatives, having the two substituents in adjacent positions (compare meta- and para-).
  4. Prefix.  (physics) of any molecule of the form X2 in which the two nuclei have parallel spin.

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This entry was last updated on RefTopia from its source on 3/20/2012.