Not expected, anticipated or foreseen. (adjective)
Examples of word unexpected
So glad the writer resisted the term "unexpected drop". sartrecastic 12 April 2011 9:59AM
Israeli commandos said they opened fire in self-defense after meeting what they called unexpected resistance when they boarded the ferry carrying aid supplies to Gaza.
The moral to this culture-jamming story: Beware banana creme and strategic and creative use of the unexpected is the perfect way to intervene.
Saudi Arabia, Egypt and Jordan have chastised Hezbollah for what they described as unexpected, inappropriate, and irresponsible acts.
This is what we call the unexpected, because no one expects them.