ゼロデイ脆弱性 ゼロデイぜいじゃくせい Meanings Noun zero-day vulnerability See also: ゼロデイ攻撃 (ゼロデイこうげき). Kanji 脆 brittle; fragile; easy to beat. Read as ゼイ. 弱 weak. Read as ジャク. 性 nature. Read as セイ. Word lists Computing Jinuma: Japanese Dictionary · Word lists