“Belt dressing” is a spray used to make fanbelts in automobiles sticky. It’s sort of opposite to WD-40. It works really well for the occasional squeaky belt. I think it goes by other names, but you can find it in your local big automotive/hardware store.
I have no idea if it would work on hinges and metal though.
Another alternative (if it’s a gate that lifts off the hinges) might be to pop a star washer (or maybe a rubber or fibre one) on the hinge posts.
use your foot.
Mangetout’s star washer/fibre washer idea is a much better idea than my silicone idea. If you can hammer the pin out of the hinge, put a fibre washer and/or a star washer in there.
As for the first question, I submit “Adhesion”
You might be able to attach a spring, such as is often used on screen doors, to the gate on one end and the gate frame or non-moving part of a hinge on its other end. The gate would then tend to stay closed, but should be easy enough to open. You can select the particular mounting point on the gate that results in the desired tension.
What about good ol’ duct tape!
My Mum rest her soul used to say that with 3 things you could fix everything.
If it moves and it shouldn’t - use duct tape.
If it doesn’t move and it should - use WD-40.
and the 3rd thing . . …
Vitamin C - It’ll keep you healthy. Fix what ails ya.
and I think the opposite of lubrication is sticky
Additionally, you could affix something (like a tennis ball, maybe) to the gate so if it does blow into your car, it won’t hurt the car [sub]as much[/sub].
I think Rucksinator’s “adhesion” is a good answer. Viscoelasticity, the noun form of viscoelastic (having appreciable and conjoint viscous and elastic properties), seems to work also.
Dessication is essentially a antonym of lubrication, but I don’t think it applies in this instance.
–Cliffy