Colloquial term for a school nurse, equivalent to the more formal 養護教諭. Often used in school settings.
The school nurse treated my injury.
The school nurse's office or infirmary. 保健医 is the person who works there.
Compound of 保健 (health) and 医 (doctor/physician). The exact historical derivation is uncertain, but the term is conventionally used for a school nurse.