The term PINT SELLER can be solved by the three letter word PUB. A PUB is a type of drinking establishment found in many countries, typically serving alcoholic drinks such as beer, wine, and spirits. Pubs are typically places of social gathering and are often used for entertainment, such as live music, karaoke, and sports viewing. The term pint seller refers to someone who works in a PUB, typically selling pints of beer or other alcoholic beverages.