1. 值勤表;勤务簿
A roster is a list which gives details of the order in which different people have to do a particular job.
2. 名单;花名册;登记表;运动员名册（尤用于美国英语中）
A roster is a list, especially of the people who work for a particular organization or are available to do a particular job. It can also be a list of the sports players who are available for a particular team, especially in American English.