An Application-Specific Integrated Circuit (ASIC) is an integrated circuit customized for a specific application, rather than being a general-purpose IC.

An Application-Specific Integrated Circuit (ASIC) is an integrated circuit customized for a specific application, rather than being a general-purpose IC.

In the context of cryptocurrencies, ASICs are generally referred to when discussing mining on Proof of Work systems. ASICs are more specialized and can be a much more efficient way of mining as compared to GPUs or CPUs.

See Wikipedia page on ASICs.