The official definition says it’s a planet if it’s big enough to be round, which IMHO is a bullshit definition because nobody cares whether your object’s round, as in, for practical settlement purposes.
As to why it’s not bullshit - the roundness is a byproduct of the object achieving hydrostatic equilibrium (which is the actual criterion, not roundness).
That’s the second out of the three points of the definition.
As to why it’s not bullshit - the roundness is a byproduct of the object achieving hydrostatic equilibrium (which is the actual criterion, not roundness).