What does the word 「しのう」 mean in this sentence?


It is said by an old man who looks like wanting to teach boxing to a young
man.

> 青山くんよ ふたりきりの人目につかんところにいこう 折り入ってひみつに伝授したいこともある **しのう**

I'm not sure if it is related to the word 死ぬ in volitional form because it
unlikely fits into the context.

