The Collaborative International Dictionary of English v.0.48:

Breakaway \Break"a*way`\, n. [Break + away] [Australasia]
   1. A wild rush of sheep, cattle, horses, or camels
      (especially at the smell or the sight of water); a
      stampede.
      [Webster 1913 Suppl.]

   2. An animal that breaks away from a herd.
      [Webster 1913 Suppl.]

   3. an object designed to break off or shatter under impact,
      as a safety measure.
      [PJC]

   4. (Sport) the sudden emergence of one or more players or
      contestants from a clustered group, rushing toward a goal,
      as bicyclists in a race, or baketball players after a
      rebound has been caught.
      [PJC]

WordNet (r) 3.0 (2006):

breakaway
    adj 1: having separated or advocating separation from another
           entity or policy or attitude; "a breakaway faction" [syn:
           breakaway, fissiparous, separatist]
    n 1: the act of breaking away or withdrawing from; "there was a
         breakaway by the discontented members"; "a breaking away
         from family and neighborhood" [syn: breakaway, breaking
         away]