A person who flattens any meaningful discussion about an event by constantly relating it back to a singleissue, e.g. income inequality, immigration, race, "Christian values," feminism, etc.
The debate moderator was asking questions about foreign policy, but Bernie Sanders just kept bringing it back to income inequality. He's a total steamtroller.
Grandma turns into a steamtroller once she starts talking about immigrants at Thanksgiving.
when someone expels gnarley butthole fumes inside a tent while camping. see also portugeuse smokehouse.
we were camping on a frosty december night, and all the windows in our tent were zipped up, when suddenely danny unleashed a brazilian steamroom of nuclear proportions.