Zero-star fare is a type of airline ticket that offers the lowest possible price for a flight. It typically does not include any additional services or amenities, such as checked baggage, seat selection, or in-flight meals. The term 'zero-star fare' is derived from the two crossword solutions SLOP (4 letters) and GLOP (4 letters). SLOP stands for 'Standard Lowest Offer Price' and GLOP stands for 'Group Lowest Offer Price'. Both terms refer to the lowest possible price for a flight.