Question

When my mother saw
her first grey hair she
thought she'd dye. Explain the pun

Answer 1

Idk I thinks means she wants to dye her hair

Answer 2

It's referring to dye as in color dye.

Step-by-step explanation:

She saw her first grey hair, which is not her natural color I'm assuming. So when she said she thought "she'd dye" the pun is referring to "dye" as in, "dye your hair". The phrase has two meanings to it, she thinks she will die, literally, but also there's a pun because her hair changed color so "dye" as in a color dye.