* Grainy describes a texture with small particles, like a photograph or a piece of bread.
* Rough describes a surface that is uneven or harsh to the touch.
Homophones need to sound the same but have different spellings and meanings. Since "grainy" and "rough" have different meanings and sounds, they cannot have a shared homophone.
Here are some potential homophones for each word individually:
* Grainy: There isn't a perfect homophone for "grainy", but "granny" could be considered a near-homophone, although it's spelled differently and has a slightly different sound.
* Rough: "Ruff" (a type of collar) is a homophone for "rough".