往おう復ふく航こう空くう券けん

Meanings

1

noun

round-trip air ticket

A ticket for a flight that includes both the outbound and return journey.

empty, sky, void

券ticket

片かた道みち航こう空くう券けん
片道航空券 is a one-way air ticket, while 往復航空券 covers both directions.
往おう復ふく切きっ符ぷ
往復切符 is a general round-trip ticket (often for trains), whereas 往復航空券 specifically refers to air travel.

Compound of 往復 (round trip) + 航空券 (air ticket).