also: てつがくはかせ
noun
Doctor of Philosophy; PhD
Refers to the academic degree, not the person holding it. The reading てつがくはくし is standard; てつがくはかせ is an older or less common variant.
彼は東京大学で哲学博士の学位を取得した。
He earned a PhD from the University of Tokyo.
哲学博士の論文を提出する締め切りは来月です。
The deadline to submit the PhD dissertation is next month.