Slip-on shoe (4)
I believe the answer is:
mule
(Other definitions for mule that I've seen before include "Obstinate quadruped" , "Sterile offspring of donkey and horse" , "Illegal drugs courier" , "Hybrid beast" , "Drug courier; animal" .)
I believe the answer is:
mule
(Other definitions for mule that I've seen before include "Obstinate quadruped" , "Sterile offspring of donkey and horse" , "Illegal drugs courier" , "Hybrid beast" , "Drug courier; animal" .)