頭の回転が速い あたまのかいてんがはやい Also written 頭の回転が早い Meanings Expression, い-adjective quick-witted; bright; rapid thinking See also: 頭の回転 (あたまのかいてん). Kanji 頭 head. Read as あたま. 回 times. Read as カイ. 転 turn. Read as テン. 速 speed. Read as はやい. Jinuma: Japanese Dictionary · Word lists