单词	optional
释义	op·tion·al (ŏpshə-nəl) adj. Left to choice; not compulsory or automatic. option·al·ly adv.
随便看	tox- toxalbumin toxaphene toxemia toxemia of pregnancy toxemic toxi- toxic toxic- decarbonize decarbonizer decarboxylase decarboxylation decarburization decarburize decare decasyllabic decasyllable decathlete decathlon Decatur Decatur decay decay chain decayer

英语词典包含135693条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。