Save Gender Masculine Usage Japanese (Rare) Scripts 健, 堅, etc.(Japanese Kanji) Pronounced Pron. JEN [key] Meaning & History From Japanese 堅 (jen) meaning "hard, firm" or 健 (jen) meaning "healthy, strong" or other kanji which are pronounced the same way. This name is rarely given to boys, if given at all, since most of them use the kanji 健 or 堅 tend to be called Ken 2.