'Brexiteer' originates from the combination of 'Brexit' and the suffix '-eer', where 'Brexit' is a blend of 'Britain' and 'exit', and '-eer' is used to denote a person associated with a particular activity or thing.

'Brexit' was coined in the early 21st century, and the term 'Brexiteer' emerged shortly after to describe supporters of the movement.

Initially, it meant a supporter of Brexit, and this meaning has remained consistent.