Objective : The using of termionology in medicine is important because terminology discriminates the meaning of words. In that aspect, there are conflicts that bao has plenty of meanings as medical terminology(womb and urinary bladder). Therefor, we need to discriminate and define bao. Method : We compare terminology of bao and words related with bao such as pao(胞) in "Dongeuibogam", "Hwangdineijing" and medical dictionary. Also we try to define right meaning of words as medical terminology. Result : Bao has several meanings in medical books. However, they have tendencies that could make scholars choose appropriate terminology in medicine. Conclusion : Bao is preferred as a womb and pao is prefferd as a urinary bladder in medical terminology.