the system of buses, trains, etc. which people use to travel from one place to another 交通运输系统
the act of going through a place on the way to somewhere else 通过；经过；通行；过境；中转
the transit lounge at Vienna airport
维也纳机场中转候机室
a transit visa (= one that allows a person to pass through a country but not to stay there)
过境签证
verb
[T, I] ~ (sth)to pass across or through an area 穿过；经过；越过
The ship is currently transiting the Gulf of Mexico.
这艘船现在正穿越墨西哥湾。