精髓 
精髓 jīngsuǐ {E} n. marrow; pith; quintessence; essence
精髓 精髓 ⑤ [jīngsuǐ] marrow; pith; quintessence; essence 
精 精 refined / - / rice blue refined 精髓 
tinh hoa; tinh tuý L5-6 精髓 jīngsuǐ (N)