sphinx
n
1 (esp 尤作 the Sphinx) stone statue in Egypt with a lion´s body and a man´s or an animal´s head 斯芬克斯(埃及的狮身人面或狮身兽面石像).
2 person who keeps his thoughts and feelings secret; enigmatic person 内心世界不外露的人; 谜一样的人
I´ve always found her rather sphinx-like. 我总觉得她像个谜一样, 难以捉摸.