posh

Unknown. Most likely derived from Romani posh (“half”), either because posh-kooroona (“half a crown”) (originally a substantial sum of money) was used metaphorically for anything pricey or upper-class, or because posh-houri (“half-penny”) came to refer to money generally. A period slang dictionary defines "posh" as a term used by thieves for "money : generic, but specifically, a halfpenny or other small coin". An example is given from James Payn's The Eavesdropper (1888): "They used such funny terms: 'brads,' and 'dibbs,' and 'mopusses,' and 'posh' ...

出典: Wiktionary「posh」（CC BY-SA 4.0）