What does this schematic symbol mean? Looks close to variable resistor
It's a fuse - a resettable PTC.

It's resistive and when it heats up because of the current flowing through it, it gets more resistive which limits the current.
When it cools down, it allows current to flow again.

The advantage is that this protects your circuit from temporary faults without having to replace the fuse because of them.
A temporary fault can be caused by the user or a specific situation like a motor that is jammed.

I accidentally tested one yesterday - it got quite hot but normal operation was restored in about 30 seconds.