英语词汇“first category”的英英意思、用法、释义、翻译、读音、例句、短语、词组-英语词典

单词	first category
释义	first category first category [′fərst ′kad·ə‚gȯr·ē] (mathematics) A set is of first category if it is a countable union of nowhere dense sets. A set S is of first category at a point x if there is a neighborhood of x whose intersection with S is of first category.
随便看	ruble society rublev rublev, andrei rublev, andrei, s. rublevo rublis rublyov rub me down rub me the wrong way rub me up the wrong way rub (multiple things) together rub my hands rub my nose in rub my nose in it rubner rubner laws rubner laws of growth rubner, max rubner's laws rubner test rubner’s laws rubner’s test rub nose rub nose in rub nose in it

英语词典包含2567994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。