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infirmary (at a school, workplace, etc.); health center; nurse's office; nurse's room; sickroom; sick bay
具合が悪くて保健室へ行った。
I felt sick and went to the nurse's office.
保健室で少し休んだ。
I rested a bit in the nurse's office.
保健室の先生に相談した。
I consulted the school nurse.