vi. Used of human behavior, conveys that the subject is
busy waiting for someone or something, intends to move instantly as
soon as it shows up, and thus cannot do anything else at the
moment.
"Can't talk now, I'm busy-waiting til Bill gets off the
phone."
Technically, 'busy-wait' means to wait on an event by
spinning through a tight or timed-delay loop that polls for
the event on each pass, as opposed to setting up an interrupt
handler and continuing execution on another part of the task. This
is a wasteful technique, best avoided on time-sharing systems where
a busy-waiting program may hog the processor.