Source : Webster's Revised Unabridged Dictionary (1913)

Nonunion \Non*un"ion\, a.
   1. Not belonging to, or affiliated with, a trades union; as,
      a nonunoin carpenter.

   2. Not recognizing or favoring trades unions or
      trades-unionists; as, a nonunion contractor. --
      {Non*un"ion*ism}, n.

Source : WordNet®

nonunion
     adj : not belonging to or not allowing affiliation with a trade
           union; "nonunion carpenters"; "a nonunion contractor"
           [ant: {union}]