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Phrase(s): horse and buggy [and] horse and carriage; buggy whip
Fig. a carriage pulled by a horse, as opposed to a modern automobile; the horse was urged on with a whip. (A symbol of old-fashionedness or out-of-dateness. Particularly with go out with, as in the examples.) • That kind of clothing went out with the horse and buggy. • I thought suspenders went out with the horse and carriage, but I see them everywhere now.
McGrawhill's American Idioms And Phrasal Verbs