Learner's definition of AIRMAIL
[noncount]
: the system used for sending mail by aircraft航空邮递 also : mail sent by using this system航空邮件 —
often used before another noun常用于另一名词前 -
an airmail letter航空信
-
airmail postage航空邮费
— airmail
verb airmails; airmailed; airmailing [+ object]