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expert; learned person
doctor; PhD; Dr.
instructor at the imperial court (ritsuryō period)
pitch and length marks (to accompany a Buddhist liturgical chant, etc.)
彼女は博士号を持っているんだ。
She has a doctoral degree.
博士課程に進学するつもりです。
I plan to go on to a doctoral program.
博士論文を書くのは大変だった。
Writing the doctoral thesis was hard.