noun
attending physician; doctor in charge
The doctor primarily responsible for a patient's care, especially in a hospital or ongoing treatment context.
主治医に今後の治療方針を確認した。
I confirmed the future treatment plan with my attending physician.
入院中は主治医の指示に
Please follow the instructions of the doctor in charge while you are hospitalized.
noun
primary care physician; family doctor; GP
One's regular doctor for general health management, often in a clinic setting. Equivalent to a family doctor or general practitioner.
風邪をひいたので、まず主治医に診てもらった。
I caught a cold, so I first saw my primary care physician.
彼女は長年、同じ主治医にかかっている。
She has been seeing the same family doctor for many years.
かかりつけ医 is a common term for a regular family doctor one visits habitually, similar to sense 2 of 主治医, but 主治医 can also refer to the attending physician in a hospital setting (sense 1).
Compound of 主 (しゅ, 'main') + 治 (じ, 'treat') + 医 (い, 'doctor'). The term is a straightforward Sino-Japanese medical compound.