AIRMAIL
airmail, airpost
(noun) a system of conveying mail by aircraft
airmail
(noun) letters and packages that are transported by aircraft
airmail
(verb) send or transport by airmail; “Letters to Europe from the U.S. are best airmailed”
Source: WordNet® 3.1
Etymology
Noun
airmail (countable and uncountable, plural airmails)
The system of conveying mail using aircraft.
The items of mail so carried.
Verb
airmail (third-person singular simple present airmails, present participle airmailing, simple past and past participle airmailed)
(transitive) To send mail by air.
(baseball) To (unintentionally) throw the ball well over a fielder's head where that fielder is unable to make a play on the ball.
Source: Wiktionary