Something of inferior quality which is included in a shipment to make up the weight.
1893, Richard Le Gallienne, in a publisher's report on stories by Ernest Dowson, quoted in Jad Adams, Madder Music, Stronger Wine, page 88.
I would advise you to accept these as an instalment of a volume, (they are not big enough to make one themselves) with the promise that the stories to come should be more striking, more original in theme — not less so, not mere makeweights — than those under consideration.
Something included to add to the apparent weight or force of an argument.
He added a long litany of peripheral precedents which the judge dismissed as mere makeweights.