1 [C] a word or symbol that indicates a quantity 数；数目；数字: Choose a number between ten and twenty. 在十和二十之间选一个数字。2, 4, 6, etc are even numbers and 1, 3, 5, etc are odd numbers. 2、4、6等是偶数，1、3、5等是奇数。a three-figure number(= from 100 to 999) 三位数

2 [C] a group of numbers that is used to identify sb/sth 号码；编号: a telephone number 电话号码a code number 代码

3 [C,U] a number (of sth) a quantity of people or things 数额；数量: a large number of visitors 大批访客We must reduce the number of accidents on the roads. 我们一定要减少道路交通事故的数量。Pupils in the school have doubled in number in recent years. 近年来学校的学生人数已多了一倍。There are a number of (= several)things I don't understand. 有几件事情我弄不懂。

4 [C] (abbr No.) (symbol #) used before a number to show the position of sth in a series （用于数字前，表示所排列的位置）: We live in Hazel Road, at number 21. 我们住在黑兹尔路21号。room No. 347 347号房间

5 [C] a copy of a magazine, newspaper, etc （杂志、报纸等的）一期: Back numbers of ‘New Scientist’ are available from the publishers. 过期的《新科学家》杂志可向出版社购买。

6 [C] (informal 非正式) a song or dance 一首歌曲；一个舞蹈