There's "Geographic north". If you look at Earth from outside its orbit, you can define the geographic north pole as the axis around which the planet rotates in a counter-clockwise direction.
The Magnetic north pole is sometimes aligned to the rotational axis , and sometimes not - depending on the type of body. The Earth's is off by a few degrees, and it's been known to flip direction in the past - it's all down to the circulation of molten metal currents in the outer core that generate the field, which changes over time. Uranus' and Neptune's fields are way off, by 40+ degrees and are even not generated in the centre of the planet.
Which one you'd actually call "north" is probably down to the individual planet's society to decide
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