essentialsn.要件；概要essentialadj.本质的；必要的；重要的n.要素；必需品essential fatty acid必需脂肪酸essential phage gene噬菌体必需基因essential convulsion[医] 中枢性惊厥essential illegality形式违法essential complexityn.本质复杂性Essential characters基本特征essential oil of hop酒花精油Essential vulvodynia原发性外阴痛essential inadequacy根本性缺陷Essential foundation实质根据