I don’t expect to get one definite answer here, but Google can’t give me one either. Some websites say they’re your second cousin, and others say they’re your first cousin once removed. I’m trying to figure out some family tree stuff so I need to know the difference between the (groups of) terms.
First cousin, once removed.
For the record, ‘once removed’ refers to the generation. Your cousin’s grandkid would be your first cousin twice removed.