頭が固い あたまがかたい Also written 頭が硬い, 頭がかたい Meanings Expression, い-adjective thickheaded; obstinate; inflexible; stubborn See also: 頭の固い (あたまのかたい). Kanji 頭 head. Read as あたま. 固 solid. Read as かたい. Jinuma: Japanese Dictionary · Word lists