round-robin
nounUK /ˌraʊnd ˈrɒbɪn/
US /ˌraʊnd ˈrɑːbɪn/
A round-robin is a game or contest where everyone plays against everyone else.
The chess club held a round-robin so every player got to face all the others.
OTHER MEANINGS
2. A letter or message sent to each person in turn, with each adding a reply before passing it on.
The neighbors kept in touch through a round-robin letter that traveled from house to house.
3. A petition or statement signed by many people with the signatures arranged in a circle so no name appears first.
The students signed a round-robin to show that everyone supported the idea equally.
4. A method of sharing tasks or turns in a fixed repeating order.
The team used a round-robin to decide who would lead the meeting each week.