1.nounA list of individuals or groups, usually for an organization of some kind such as military officers and enlisted personnel enrolled in a particular unit; a muster roll; a sports team, with the names of players who are eligible to be placed in the lineup for a particular game; or a list of students officially enrolled in a school or class.
2.nounA list of the jobs to be done by members of an organization and often with the date/time that they are expected to do them.
"The secretary has produced a new cleaning roster for the Church over the remainder of the year."
3.verbTo place the name of (a person) on a roster.
"I have rostered you for cleaning duties on the first Monday of each month."