Denshi Jisho — Online Japanese dictionary

驢 ろ donkey
Noun 
驢馬 ろば donkey; ass
Noun, No-adjective, Usually written using kana alone 
驢車 ろしゃ donkey cart
Noun, Obscure term 
驢 うさぎうま donkey
Noun 
兎馬 うさぎうま donkey
Noun 
驢馬の橋 ろばのはし pons asinorum (hurdle to learning)
Noun 

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