great scholar; savant; polymath
Refers to a person of great learning and wide-ranging knowledge, often with a connotation of eminence.
He is a great scholar well-versed in everything from literature to science.
碩学 is a more formal and literary term for a 'great scholar', often used in academic contexts.
Compound of 大 (dai, 'great') + 学者 (gakusha, 'scholar').