one-drinking
n.— «One-drinking: In bar parlance, one-drinking refers to a group that turns one trip into 10 for a server by requesting items one at a time.» —“Here’s taste of often unsavory business of waiting tables” by Howard Seftel Arizona Republic (Phoenix) Oct. 19, 2005. (source: Double-Tongued Dictionary)
Further reading
Book recommendations and the art of apology. Martha and Grant share some good reads, including an opinionated romp through English grammar, a Spanish-language adventure novel, an account of 19th-century dictionary wars, and a gorgeously illustrated...
Secret signals on the job: Waitresses at some 19th-century restaurants ensured speedy drink service by communicating with a non-verbal code. One server took orders, then placed each customer’s cup to indicate exactly what the customer wanted...