Thumb method cast on?

My pattern called for adding stitches using the thumb method of casting on, and I am wondering how to do it. I didn’t see instructions for any cast-on methods called by that name. So I faked it.
Anybody know what it is, or what else it might be called that I might recognize by name?? Thanks!

I think it probably means the Backward-Loop Cast-On. I’ve seen it used when you add a bunch of stitches to one end of your knitting. There’s a video on this site. Amy doesn’t use her thumb but it’s the same idea.

It might also mean the longtail caston, but usually it doesn’t matter how you cast on. So don’t be afraid to stitck with whatever you find easiest, unless another cast-on is really indicated.

Thumb method is a variation of longtail CO, but since it’s to add sts to what you’ve already got, they probably mean the backwards loop. I use my thumb for that one.