domestique
A cyclist on a cycle racing team whose role is to assist the team's designated leaders (for example, by riding in front of them to create a slipstream, or to set the pace), even if at the expense of their own individual performance.
In a recent poll [Sean] Yates was voted one of the top-10 domestiques of all time, a crucial cog to any leader's Tour ambitions. […] To many casual observers, the role of domestique is not a particularly rewarding one. Yates begs to differ.
Where it comes from
Borrowed from French domestique (“domestic servant, maid”), from domestique (“domestic”, adjective), from Latin domesticus (“of the house, domestic; familiar; native”), from domus (“home, house; place of one's birth or residence, native country”). Doublet of domestic.
Adapted from the Wiktionary entry domestique (CC BY-SA 4.0).