Definition of "leaver"

An extraordinary cross-party summit bringing together leading leavers and remainers – including Michael Gove and senior members of Keir Starmer’s shadow cabinet – has been held in high secrecy to address the failings of Brexit and how to remedy them in the national interest, the Observer can reveal.

2023 February 11, Toby Helm, “Revealed: secret cross-party summit held to confront failings of Brexit”, in The Observer‎