This is the 4108th most frequent Russian word.
поезд
Train.
Here, 'поезд' is used as the subject of the sentence, meaning the mode of transport 'train'.
Поезд шёл мимо станции.
The train went past the station.
In this sentence, 'поезд' denotes the destination-linked train mentioned in the context.
Я забронировал билет на поезд в Москву.
I booked a ticket for the train to Moscow.
The word here relates to 'поездка', which originates from 'поезд', showing a derived root referring to a journey.