From Wikipedia:

The peloton (from French, literally meaning little ball or platoon and also related to the English word pellet), field, bunch or pack is the large main group in a road bicycle race. Riders in a group save energy by riding close (drafting or slipstreaming) near (particularly behind) other riders. The reduction in drag is dramatic; in the middle of a well-developed group it can be as much as 40%.

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