Definitions
1.nounA mischievous child.
2.nounA street urchin, a child who lives, or spends most of their time, in the streets.
3.nounA sea urchin.
4.nounOne of a pair in a series of small card cylinders arranged around a carding drum; so called from its fancied resemblance to the hedgehog.
5.nounA neutron-generating device that triggered the nuclear detonation of the earliest plutonium atomic bombs.
6.nounA hedgehog.
7.nounA mischievous elf supposed sometimes to take the form of a hedgehog.