When you're in a zone and you're only able to hear what your mind is focused on. Others think you're ignoring them when they talk but the truth is they failed to gain your attention first.
My wife swears I was ignoring her but I have selective hearing, my attention was on the TV and I was completely unaware she was talking to me.
The ability that humans have, especially males, to hear selectively only what serves their interests, being conveniently deaf to what they don't like or can use.
"I asked John to take the trash out and then get a beer from the fridge; of course he went straight for the beer: he has selective hearing".