Whispering
Noun
ないしょばなし
当人達は内緒話をしているつもりのようだが、声がでかいので全部筒抜けだよ。
They are trying to whisper to each other, but their voices are so loud that I can hear everything.
The inside together talk is talk that's only inside between us. It's confidential talk.
This word uses the on'yomi of 内緒 and kun'yomi of 話, only rendakued.