Wiktionary
undergrounders
n. (plural of undergrounder English)
Wikipedia
Undergrounders
Undergrounders is a novel written by Canadian author David Skuy, published by Scholastic Canada in 2011 and winner of the 2012 Silver Birch award.
Usage examples of "undergrounders".
Something, as it happened, turned up very soon, for as Speedy and Marygolden entered the public square of Subterranea, a crowd of undergrounders, catching sight of them, forgot to whisper and burst into earsplitting shrieks and yells.
From their expressions, none of the students had actually met any of the undergrounders before.
Marygolden, more interested than alarmed, pressed her pretty face against the window glass, but Speedy, as the undergrounders with bars and clubs fell upon the torpedo, began to feel terribly anxious.