In general terms posh means wealthly people,elegant,luxurious house.The origin word come 1915-1920,of obscure origin; compare a dandy (recorded as Britain slang is 1890) the word posh is an acronym from port out (ward),starboard home,said to be the preferred accomodation on ships travelling between England India,is without foundation.
    In the northern working class girl  the accent is different from the urban Upper class girl when the northern working class say hello they usually miss the'h' and somethime it is difficult to understand when they speak.Normally,urban upper class girl are posh that means they are very sophisticate,well believed in front of puplic,they talk less,well dress.Moreover,they talk about moneyand about wealthly people.No,any of the differences particularly did not surprised me.
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