Nonunion \Non*un"ion\, a. 1. Not belonging to, or affiliated with, a trades union; as, a nonunion carpenter. [Webster 1913 Suppl.] 2. Not employing trade union members; not recognizing or favoring trades unions or trades-unionists; as, a nonunion contractor; a nonunion subcontractor. -- {Non*un"ion*ism}, n. [Webster 1913 Suppl.]