Grandma dealt with this problem on a regular basis. Home canned jars are notorious for being hard to open. That’s because in the home canning process, canning liquid often gets sucked up into the lid area and dries.
But even a store-bought jar can be hard to open.
1. Is there a man/and/or/teenager with big, strong hands around? If so, ask him to open the jar. This will make him feel good about himself.
2. Get traction. Wrap rubber bands, (the kind that come on broccoli work well) around the lid to give it some grabbyness. A piece of rubbery shelf liner works too.
The Damsel has even heard of a person using a mouse pad. He got the lid open and also felt happy that his mouse pad actually did something useful.
3. Run hot water over the lid area. This not only loosens any dried stuff, but expands the metal a bit so it will let go of the glass a little easier. The Damsel saves this one for last because once the jar is wet, everything is slippery.
4. There are other ways, like prying around the lid with a spoon or can opener to lessen the vacuum. Some folks hit the jar with things; others hit the jar against things. People even stab the lid with a knife, thus relieving the vacuum. This gives the Damsel an uncomfortable feeling inside.
Let’s not open that can of worms.