usage guiden. a book of instruction or information relating to the conventionally accepted use of (esp. formal written) language and grammar.
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1951 College Composition & Communication2 17/1 There should be a reference library of dictionaries, handbooks, usage guides..and other pertinent material.
2007 Globe & Mail (Toronto) (Nexis) 17 May r1 The increasingly liberal usage guides are so cautious about prescribing anything these days.