People who enter a train and get stuck at the door forcing everyone else to have to squeeze past them even though there's ample space further inside the compartment. Sort of like lint in the dryer.

See also, train lint catcher - a person who yells at train lint to move further in and stop blocking the door.
Man there was so much train lint on the 9:02 this morning, I feel like I've been in a mosh-pit. We could've really used a train lint catcher.
by jeamish February 25, 2021
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