The Collaborative International Dictionary of English v.0.48:

React \Re*act"\ (r[=e]*[a^]kt"), v. t.
   To act or perform a second time; to do over again; to
   reenact; as, to react a play; the same scenes were reacted at
   Rome.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

React \Re*act"\ (r[-e]*[a^]kt"), v. i.
   1. To return an impulse or impression; to resist the action
      of another body by an opposite force; as, every body
      reacts on the body that impels it from its natural state.
      [1913 Webster]

   2. To act upon each other; to exercise a reciprocal or a
      reverse effect, as two or more chemical agents; to act in
      opposition.
      [1913 Webster]

WordNet (r) 3.0 (2006):

react
    v 1: show a response or a reaction to something [syn: react,
         respond]
    2: act against or in opposition to; "She reacts negatively to
       everything I say" [syn: react, oppose]
    3: undergo a chemical reaction; react with another substance
       under certain conditions; "The hydrogen and the oxygen react"