Wiktionary
n. An animal that leaves its eggs in the nest of others to be raised.
Wikipedia
Brood parasitism relieves the parasitic parents from the investment of rearing young or building nests for the young, enabling them to spend more time on other activities such as foraging and producing further offspring. Bird parasite species mitigate the risk of egg loss by distributing eggs amongst a number of different hosts. As this behaviour damages the host, it often results in an evolutionary arms race between parasite and host.
Usage examples of "brood parasite".
One of the ever-vigilant Nurses who feed and tend the larvae had rushed to devour him as a brood parasite, and Costard had burst his flask of brood scent (a precautionary measure every tapper goes equipped for) at the last possible instant.