down line noun 3down-line adjective 1forms 4 noun3 •[before a noun] A member or members of a multi-level marketing scheme recruited by another (their up line) and paying that recruiter a portion of their earnings.I declared to everyone that I would concentrate on selling, not on recruiting, and build my downline slowly over time. — 1998 •A railway line on which trains travel away from a major terminus.The down line was cleared about midnight, or nine hours after the accident, but the up line was not in a state to admit of the traffic being resumed until one o'clock on the next day. — 1857 •the next and subsequent flights in an itinerary.If you miss a flight, the airline will likely cancel the down line. down-line adjective1 •Describing a lower level in a hierarchical management structure formsdown lines · down-lines · more down-line · most down-line