This is the 6216th most frequent Russian word.
транспортом
"Транспортом" translates to "by transport" in English.
Here, 'транспортом' is the instrumental case of 'транспорт', indicating the means or tool by which an action is performed.
Мы быстро добрались туда на общественном транспортом.
We quickly got there by public transport.
In this sentence, 'транспортом' is used in the instrumental case as part of the fixed expression 'увлекаться чем-либо', meaning 'to be fascinated by something'.
Он увлекается общественным транспортом и знает все маршруты.
He is fascinated by public transport and knows all the routes.
Here, 'транспортом' expresses the means of transportation, indicating the tool for the action.