Ok, it isn’t technically a word, more like two, but the idea of it is so lovely.
Basically a whispering gallery is a circular area beneath a dome that allows whispers from one side to be heard clearly at the other.
There is one near the Oyster Bar at Grand Central Station in New York. It is at the junction of four walkways. You stand facing the corner while your friend/lover/random stranger stands in the opposite one.
Whisper away and it will sound as if you are right next to person instead of over the other side of the room.
Apparently such galleries are often used for marriage proposals or for whispering sweet nothings.
That didn’t happen to me.