conflict miss
A miss because too many busy lines want the same group of slots, even though other parts of the cache are free.
A conflict miss is a miss that a fully associative cache of the same size would have avoided; it arises when more than N active blocks map to one set of an N-way cache. Higher associativity, or changing the stride, removes it.
Examples
Two arrays exactly 32 KiB apart map to the same lines of a 32 KiB direct-mapped cache and keep evicting each other.
See also