posh 1
/posh/ , adj.
sumptuously furnished or appointed; luxurious: a posh apartment.
[ 1915-20; of obscure orig.; cf. posh a dandy (recorded as British slang in 1890); the popular notion that the word is an acronym from port out ( ward ), starboard home, said to be the preferred accommodation on ships traveling between England and India, is without foundation ]
posh 2
/posh/ , interj.
(used as an exclamation of contempt or disgust.)
[ 1920-25 ]