Teardrops are pretty rare (See Driving All Night, October 2017.) and permit aircraft to reverse course and lose a significant amount of altitude within a defined area (these are often found at military or joint-use airports). These are entered at the initial fix, proceeding outbound on the defined radial, and initiating a turn inbound at the defined point or distance. Think of it as a conventional procedure turn, but usually much larger and with explicitly defined segments.