WebA number is a mathematical object used to count, measure, and label. The original examples are the natural numbers 1, 2, 3, 4, and so forth. Numbers can be represented in language with number words. More universally, individual numbers can be represented by symbols, called numerals; for example, "5" is a numeral that represents the number five.
Webc (1) : a member of a sequence or collection designated by especially consecutive numbers (such as an issue of a periodical) just received issue number 8 of the magazine. (2) : a position in a numbered sequence. You're number 7 on the waiting list.