Well, based on the definition of:
A deadlock is a situation wherein two or more competing actions are each waiting for the other to finish.
I would say that the answer is no – sure a thread can sit there waiting indefinitely for something, however unless two competing actions are waiting for each other it is by definition not a deadlock.
Unless someone explains to me how a single thread can be simultaneously waiting for two actions to finish?
UPDATE: The only possible situation that I can think of is some sort of message pump, where a thread processes a message that asks it to wait indefinitely for something to happen, where in fact that something will be processed by another message on the message pump.
This (incredibly contrived) scenario could possibly be technically called a deadlock.