category killer
noun[C]
informalukusCOMMERCE
aproduct,service,store, etc. that is sosuccessfulthatsimilarproducts,businesses, etc.failbecause they cannotcompete:
Some 6,000smallretailershave beenforcedtoclosebycategorykillerstores.
Ebay is one of the mostobviousonlinecategorykillers.