noun
or ka·tab·o·lism kəˈtabəˌlizəm
( -s )
Etymology: Greek katabolē throwing down (from kataballein to throw down, from kata- cata- + ballein to throw) + English -ism — more at devil
: destructive metabolism involving release of energy and resulting in true excretion products although certain new substances may be formed in metabolic processes that are mainly catabolic — opposed to anabolism