also: トレーンジャック
noun
train ad takeover; using all ad space in a train car
Wasei-eigo term for the practice of buying all advertising space inside a single train carriage, often for a promotional campaign.
wasei-eigo (Japanese-coined English), from trainjack
今月、山手線でトレインジャック広告が展開されている。
This month, a train ad takeover campaign is running on the Yamanote Line.
トレインジャックは、車内のすべての広告枠を一社で占有する手法だ。
A train ad takeover is a method where one company occupies all the advertising space inside a train car.