profound; extensive (knowledge)
Formal, literary word describing deep and wide-ranging knowledge or scholarship. Often used in academic or intellectual contexts.
He has profound and extensive knowledge.
I am amazed by the professor's profound scholarship.
The word 該博 is composed of 該 (broad, extensive) and 博 (wide, learned). The exact historical derivation is uncertain, but the kanji combination conveys the meaning of wide-ranging and profound knowledge.