Resistance is a measure of the… resistance of flow of electricity. Let’s try that again without breaking a cardinal rule of definitions. Resistance is how much the electrons struggle to move in comparison to the voltage across something. So, if there’s high voltage and high resistance, there will be low current, just as if there’s low voltage but low resistance. There. Hopefully that’s better.
The ability to resist the flow of electric current; it is measured in ohms.
Fundamentals of Electric Circuits, 5th Edition by Charles K. Alexander and Matthew N. O. Sadiku
The opposition to the flow of current in an electric circuit.
Grob’s Basic Electronics, 11th Edition by Mitchel E. Schultz