"loop" - key terms from Wikipedia

business loop
causal loop	diagram
chicago loop
circumlunar loop
closed loop
control loop
current loop
dive loop
end loop
eventually reach the loop
feedback loop
freeway loop
ground loop
immelmann loop
infinite loop
inner loop
launch loop
local loop
loop
loop	body
loop	diuretic
loop	diuretics
loop	field
loop	jump
loop	of henle
loop	quantization
loop	quantum gravity
loop	ramps
loop	systems
loop	tuning
loop	variable
main loop
open loop
open loop	systems
outer loop
penalty loop
pid loop
positive feedback loop
primary loop
reactive site loop
secondary loop
south loop
state highway loop
strange loop
time loop
toe loop
toe loop	jump
triple toe loop
vertical loop
while loop