外卖 = takeout,
骑手 = rider (originally horse rider / jockey). The term is pervasive thanks to
美团 and
饿了么's armies of scooter couriers. A 2020 Renwu magazine article
《外卖骑手,困在系统里》 ('Delivery riders, trapped in the system') triggered a national debate about algorithm-driven working conditions in the gig economy.