We have positions one through ten in Google, the main search results. We have position zero, the featured snippets. Heck, we even have zero results where Google just shows the answer.
Now we have position minus one or screen -1 as Google's Malte Ubl called it on Twitter yesterday. Malte who is big with the AMP team said "Google’s Discover product (the -1 screen on Android among other surfaces)." He was talking about the new Google Discover report and calling Google Discover the -1 screen.
So far Google’s Discover product (the -1 screen on Android among other surfaces) looked like Search traffic in Analytics software, because it is using the same referrer. Search Console now splits out Discover traffic, so you can see the split for your site https://t.co/JMPNFm7jyT
— Malte Ubl (@cramforce) April 10, 2019
It makes sense - it is search results without the query. So it happens even before you do a search and thus it is a predictive thing.
So there you go, we can call Google Discover traffic position minus one. I think it has a ring to it...
Forum discussion at Twitter.