In the 18th century, POSH was stamped on luxury liner passenger luggage on trips from England to India. These wealthy passengers wanted the best accommodations onboard, which meant on the voyage from England they wanted to be on the left side of the ship (port), and on the return trip on the right side (starboard). Port out, Starboard Home was shortened to POSH. When others saw "POSH" on the luggage, they knew this was a special person who had nice things.
Would you share the unusual origin of a commonly used word that might surprise us?