do by someone or something do by someone or something {v.} To deal with; treat. — Used with a qualifying adverb between "do" and "by". Andy's employer always does very well by him. Categories: add yours {v.} Source: A Dictionary of American Idioms by A. Makkai, M.T. Boatner, J.E. Gates © 2024 To section: D Subscribe to: American IdiomsIdioms feedEnglish languageHome page and general feed Add my comment