プログレッシブ和英中辞典(第4版)の解説
あとあし【後足】
〔動物の〕hind [back] legs
熊が後足で立った
The bear stood up on its hind legs.
砲声を聞いて馬は後足で立った
The horse reared up at the roar of the gun.
犬が後足で砂を掛けた
The dog kicked up the dirt with its hind legs.
後足で砂を掛ける
do something malicious to a person when departing [leaving]; take a parting shot at a person