1. not scheduled or not on a regular schedule; - Example: "an unscheduled meeting" - Example: "the plane made an unscheduled stop at Gander for refueling"
WordNet (r) 3.0 (2006):
unscheduled
adj 1: not scheduled or not on a regular schedule; "an
unscheduled meeting"; "the plane made an unscheduled stop
at Gander for refueling" [ant: scheduled]