Unknown; popularly (but falsely) believed to be an acronym for "port out, starboard home", describing the cabins given to upper-class passengers travelling with the Peninsular and Oriental Steam Navigation Company from Britain to India and back. The company denies this practice, despite christening its loyalty scheme the "P.O.S.H. Club" after the myth (the club has since been renamed "Portunus"). A more likely origin is the Romany word posh meaning "half-", as in posh-kooroona meaning "half a crown" - a once-substantial sum of money, and hence by association anything pricey or upper-class. Alternatively posh may have first become a general term for money, after posh-houri, half-penny. See 1 for other theories.
Posh!
Category:Unknown etymology
fr:posh io:posh vi:posh zh:posh