A language is a dialect with an army and navy

"A language is a dialect with an army and navy" is a quip or humorous adage about the arbitrariness of the distinction between a dialect and a language. It points out the influence that social and political conditions can have over a community's perception of the status of a language or dialect. The adage was popularized by the sociolinguist and Yiddish scholar Max Weinreich, who heard it from a member of the audience at one of his lectures.

This statement is usually attributed to one of the leading figures in modern Yiddish linguistics, Max Weinreich, who expressed it in Yiddish:

The earliest known published source is Weinreich's article Der YIVO un di problemen fun undzer tsayt (דער ייִוואָ און די פּראָבלעמען פֿון אונדזער צײַט "The YIVO Faces the Post-War World"; literally "The YIVO and the problems of our time"), originally presented as a speech on 5 January 1945 at the annual YIVO conference. Weinreich did not give an English version.

In the article, Weinreich presents this statement as a remark of an auditor at a lecture series given between 13 December 1943 and 12 June 1944:

A teacher at a Bronx high school once appeared among the auditors. He had come to America as a child and the entire time had never heard that Yiddish had a history and could also serve for higher matters.... Once after a lecture he approached me and asked, 'What is the difference between a dialect and language?' I thought that the maskilic contempt had affected him, and tried to lead him to the right path, but he interrupted me: 'I know that, but I will give you a better definition. A language is a dialect with an army and navy.' From that very time I made sure to remember that I must convey this wonderful formulation of the social plight of Yiddish to a large audience.

The sociolinguist and Yiddish scholar Joshua Fishman suggested that he might have been the auditor at the Weinreich lecture, and has subsequently been cited as the originator of the army-navy statement in several references. However, Fishman was assuming that the exchange took place at a conference in 1967, more than twenty years later than the YIVO lecture (1945) and in any case does not fit Weinreich's description.

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