Wikipedia
Open loop
An open loop is a rhetorical device to instill curiosity by creating anticipation for what will come next. The device is sometimes also called a tension loop for the tension and anticipation it creates.
Usage examples of "open loop".
Roland had taken it off the rawhide string, which now lay in an open loop around his neck.
He dropped the open loop at the end of the lariat clear of his fingertips, and opened the loop wider with the practiced, expert motions his hands had learned through years of dealing with the large, stubborn, aggressive rams of his uncle's mountain sheep.
One end was a simple open loop and the other held the teeth of a standard door key.
Laurence shouted, pointing to the nearest open loop of the carrying-harness, and caught the man’.