Half man, half moth. A moth size insect who's head has been replaced by a mans head. First inverted by Karl Pilkington when he misheard Steven Merchant say the word mammoth.

Can be heard in an episode of the XFM radio station Ricky Gervais Show on 24 August 2002
A manmoth is "mans head, moths body, bumping into lights and stuff"
by zapras April 30, 2011
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