Relating to or practicing cannibalism; involving the consumption of human flesh by humans.
From 'cannibal' plus '-istic' (meaning characterized by or of the nature of). This is the standard English adjectival form, fully established by the 19th century.
Cannibalistic isn't always literal—ecologists use it to describe animals that eat their own species, and companies engage in 'cannibalistic' behavior when one product destroys their other products' sales!
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