I'm not sure if this is an herb but it was given to me with some White Sage and Parsley so I thought it might be. It has really big bulb like roots.
Here is a link that might be useful:
I can't tell from this picture. Do you have any other details about the plant? Like do you know if it blooms or does it have a scent?
It's not parsley or any sage I know of. Kinda looks like Liriope.
If the stem in the top middle of the photo is not part of it, could it be lemongrass?
You could crush a small piece of leaf and check the fragrance....