Quiz: Remember the definition of mal de mer?
1610s, "part of a city to which Jews were restricted," especially in Italy, from Italian ghetto "part of a city to which Jews are restricted," various theories of its origin include: Yiddish get "deed of separation;" special use of Venetian getto "foundry" (there was one near the site of that city's ghetto in 1516); a clipped word from Egitto "Egypt," from Latin Aegyptus (presumably in memory of the exile); or Italian borghetto "small section of a town" (diminutive of borgo, of Germanic origin, see borough). Extended by 1899 to crowded urban quarters of other minority groups (especially blacks in U.S. cities). As an adjective by 1903 (modern slang usage from 1999). Ghetto-blaster "large, portable stereo" is from 1982.