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When in Rome, do as the Romans do

Cultural  

  1. When visiting a foreign land, follow the customs of those who live in it. It can also mean that when you are in an unfamiliar situation, you should follow the lead of those who know the ropes.

when in Rome do as the Romans do Idioms  

  1. Follow local custom, as in Kate said they'd all be wearing shorts or blue jeans to the outdoor wedding, so when in Rome—we'll do the same. This advice allegedly was Saint Ambrose's answer to Saint Augustine when asked whether they should fast on Saturday as Romans did, or not, as in Milan. It appeared in English by about 1530 and remains so well known that it is often shortened, as in the example.

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.