fanatic
/fəˈnætɪk; fə`nætɪk/ n
person who is too enthusiastic about sth, esp religion or politics 狂热者（尤指在宗教或政治方面）
a religious, political fanatic 宗教狂、 政治狂
model train fanatics 对模型火车入迷的人. fanatic (also fanatical / -kl; -kl/), adj ~ (about sth) obsessively enthusiastic 狂热的
a fanatic jogger 极喜欢慢跑的人
She's fanatical about keeping fit. 她如醉如痴地注重健美.