Early 20th century: perhaps from slang posh, denoting a dandy. There is no evidence to support the folk etymology that posh is formed from the initials of port out starboard home (referring to the more comfortable accommodation, out of the heat of the sun, on ships between England and India).

• One of the more frequently repeated explanations of the origin of a word is the story that posh, comes from the initials of ‘port out, starboard home’. This is supposed to refer to the location of the more desirable cabins—on the port side on the outward trip and on the starboard side on the return—on passenger ships between Britain and India in the 19th century. Such cabins would be sheltered from the heat of the sun or benefit from cooling breezes, and so were reserved by wealthy passengers. Sadly, there is no evidence to support this neat and ingenious explanation. The P&O steamship company is supposed to have stamped tickets with the letters P.O.S.H., but no tickets like this have ever been found. A more likely explanation is that the word comes from a 19th-century slang term for a dandy, from thieves' slang for ‘money’. The first recorded example of posh is from a 1915 issue of Blackwood's Magazine.