mushroom
1. mush.room \'m*sh-.ru:m, -.ru.m\ n [ME musseroun, fr. MF mousseron, fr.
LL mussirion-, mussir] often attrib io 1a: an enlarged complex aerial
fleshy fruiting body of a fungus (as of the class Basidiomycetes) that
consists typically of a stem bearing a flattened cap; esp : one that is
edible 1b: FUNGUS archaic 2: UPSTART 3: something resembling a mushroom
2. mushroom vi 1: to spring up suddenly or multiply rapidly of a bullet
2a: to flatten at the end at impact 2b: to well up and spread out
laterally from a central source