If you describe someone or something as a makeweight, you think that they are not good or valuable and that they have been included in an activity in order to fill up a gap.
[disapproval]
He has not been signed to the club as a makeweight to fill out the numbers.
makeweight in British English
(ˈmeɪkˌweɪt)
noun
1.
something put on a scale to make up a required weight
2.
an unimportant person or thing added to make up a lack
makeweight in American English
(ˈmeɪkˌweɪt)
noun
1.
anything added to a scale to complete the required weight
2.
an unimportant person or thing added to make up some lack