At Yahoo! Respuestas en Español I recently found this exchange (in which I’ve made some corrections):
Spanish has indeed taken to using the English word snob, which is often spelled esnob to reflect the actual Spanish pronunciation. Unfortunately the proposed etymology as an abbreviation of the Latin phrase s[in] nob[ilitate] ‘without nobility’ is itself without any nobility, which is fancy way for me to say that there’s no truth to it, which is a polite way of saying that it’s a lie. Such made-up explanations for the origins of words or phrases are often called folk etymology, which may sound folksy but still means that the would-be explanation is false.
The earliest known occurrence in print of snob was 1781, when it meant ‘shoemaker, cobbler.’ By the 1796, students at Cambridge had begun using the word as slang to refer to ‘a townie,’ ‘someone not connected to the university.’ (Note that the earlier usage in the sense of ‘shoemaker,’ before the word became university slang, kills the folk etymology of sin nobilitate.) In the 1830s, according to John Ayto in Word Origins, the sense was ‘member of the lower orders’ and then ‘ostentatiously vulgar person.’ In 1848, the novelist William Thackeray published Book of Snobs, where he used the term to mean ‘someone vulgarly aping his social superiors.’ Finally came the modern sense of snobs as ‘people who think they’re better than others, usually because of their social class.’ Interestingly, the definition of esnob in the DRAE is still Thackeray’s of ‘Persona que imita con afectación las maneras, opiniones, etc., de aquellos a quienes considera distinguidos.’
As for slob, which as far as I can tell Spanish hasn’t borrowed, the American Heritage Dictionary gives this etymology: “Irish Gaelic slab, mud, from Old Irish, probably of Scandinavian origin; akin to Swedish dialectal slabb, mud.”
© 2013 Steven Schwartzman