roaming
noun [ U ] uk/ˈrəʊ.mɪŋ/ us/ˈroʊ.mɪŋ/
（手机）漫游
the use of a mobile phone service that you can connect to when you cannot connect to the one that you normally use, for example if you are in another country
You will face extra costs for roaming. 手机漫游会额外收费。
Beware of roaming charges of up to $3 a minute. 小心漫游费可能高达每分钟3美元。