cannibalize

Concise Oxford English Dictionary © 2008 Oxford University Press:
cannibalize /ˈkanɪbəlʌɪz/ (or cannibalise)

▶verb

• 1 use (a machine) as a source of spare parts for another, similar machine.

• 2 (of a company) reduce (the sales of one of its products) by introducing a similar, competing product.

• 3 (of an animal) eat (an animal of its own kind).

– derivatives
cannibalization noun.