孺子牛

rúzǐniú

(1) [an adult dressed up as an ox in a children's game]∶儿童游戏时牵着走的由大人扮成的牛

(2) [a man who is willing to serve the people]∶比喻甘愿为人民大众服务的人

横眉冷对千夫指, 俯首甘为孺子牛。 --鲁迅诗