I was playing sprouts with a few friends the other day, and one of them tried to be clever by "squeezing" their line next to another player's line to effectively prevent any passthrough play:
Now, I'm pretty terrible with the trackpad in paint, so bare with my low quality art here. The focus is the upper right area where the red and blue lines look like they're intersecting (just imagine they aren't as it's a side effect of my terrible paint skills). The idea the red player had was to shrink the playable region between their line and the blue player's line as much as possible, effectively closing the area off.
However, this annoyed both myself (green) and the red player. Since none of us could truly determine if the rules permitted this movement, we all agreed at the time that since the rules prevent intersection, the space between the red and blue lines was just really small. As such, pass through could still occur with the understanding that the line passing through would "shrink" into the space and expand back to normal size on the other side, effectively simulating a pass through without intersection.
Unfortunately though, my curiosity is getting the better of me and now I'm wondering if it's wrong to assume this since two objects must overlap to be considered an intersection, by definition:
(of two or more things) pass or lie across each other.
Or not? If the outermost edges of two objects only touch, is it technically an intersection?
Edit: For close votes related to this being off-topic due to not being about mathematics; my question isn't focused on the game of sprouts, but rather something I encountered during play that I was looking for clarification on. That something is terminology related to intersection and is mathematics related.