Sentence:  Consider the “<WSD>cinchy</WSD>" horse. You tighten the girth and he blows up against it. By the same token, if you use a death grip with your legs on your horse's sides to ask him to go forward, he might swell up against you like the <WSD>cinchy</WSD> horse and be less forward. 
Meaning of the word marked with <WSD> tags:  Tending to fight having a girth cinched.