Airmail; mail sent by air (air mail).
クリスマスカードを航空便で海外の友人に送った。
I sent Christmas cards to friends abroad by airmail.
国際小包は通常、航空便で届くまで数日かかる。
International parcels usually take a few days to arrive by airmail.
急ぎの書類は航空便で送った方が安全だ。
It's safer to send urgent documents by airmail.
Air service; air transport of goods and mail (air freight/shipping).
部品を急いで届けるために航空便で輸送した。
We shipped the parts by air service to deliver them quickly.
路線の拡大で主要都市間の航空便が増えた。
With route expansion, air service between major cities has increased.