haunch 
/ˈhɑ:ntʃ/ noun
plural haunch·es /ˈhɑ:ntʃ/ noun [count] : the upper part of a person's or animal's leg ; especially : the upper part of an animal's rear leg used as meat
▪ a haunch of venison
▪ a haunch of venison
on your haunches
: sitting on or close to your heels with your knees bent
▪ The girl was sitting/squatting on her haunches in the sand, searching for shells.
▪ The girl was sitting/squatting on her haunches in the sand, searching for shells.
