I think you’ve hit the nail on the head there, we need to contact Patsy Kensit. Her decision is final.
Let’s say I’m on the back wheel struggling to keep my balance and I hop left a bit, right a bit, forward a bit, backwards a bit.... have I done a left-hop, right-hop, front-hop and back-hop No, I’ve just done four back-hops, each in a different direction.
‘Back’ refers to the wheel in question.
To further cement this point, front-hops are hops done on the front wheel aren’t they, regardless of the direction you’re travelling in? If I use your definition, I could back-hop (hop backwards) on my front wheel couldn’t I?