prefix

1. N-COUNT A prefix is a letter or group of letters, for example, "un-" or "multi-," that is added to the beginning of a word in order to form a different word. For example, the prefix "un-" is added to "happy" to form "unhappy." Compare and . 前缀

2. N-COUNT A prefix is one or more numbers or letters added to the beginning of a code number to indicate, for example, what area something belongs to. 前置代码

To telephone from the U.S. use the prefix 011 33 before the numbers given here. 从美国拨出电话，请在所给号码前加拨前置代码011 33。