Example sentences
jī机chǎng场zěn怎me么qù去？
How do I get to the airport?
wǒ我qù去jī机chǎng场jiē接rén人。
I'm picking someone up at the airport.
About this word
机 is "machine" and 场 is "open ground", so 机场 is literally a field for machines. The machine in question is 飞机, "flying machine", the airplane, and once you have that, words like 手机 (hand machine, mobile phone) and 洗衣机 (wash machine, washing machine) stop looking random. Chinese sorts its transport hubs by shape: open ground takes 场, so airports and playgrounds are 场, while stops along a route take 站. The longer form 飞机场 is also correct and slightly more conversational.
The story behind the character
机
机 is 木 (wood) with 几 on the right giving the sound. The traditional form is 機, and its first meaning was the trigger of a crossbow, a small wooden mechanism that releases the shot. Xu Shen wrote 機，主發謂之機: the thing in charge of releasing. Every machine since is a descendant of that trigger.
场
场 is 土 (earth) with 昜 on the right, which gives the sound. Xu Shen defined the traditional 場 as 祭神道也, the swept path used for sacrifices. Flat, cleared ground set aside for one purpose. That is the sense still alive in 机场: a wide flat place, now for planes instead of offerings.