canibalizar

To cannibalize — used both literally (an animal eating its own species) and, very commonly in business and marketing, figuratively: a new product cannibalizing the sales of an existing one from the same company.

• El nuevo modelo canibalizó las ventas del anterior. — The new model cannibalized sales of the previous one.
• Algunos peces pueden canibalizar a sus crías. — Some fish can cannibalize their own young.
• La marca teme canibalizar su propio mercado. — The brand fears cannibalizing its own market.

In everyday business Spanish this almost always means one product or service eating into another's sales, not literal cannibalism — context (products, sales, markets) should make the figurative sense clear.