The term "earthlike" needs several conditions to be met. It must be a hard surfaced (rocky) planet not a gas giant. It must be large enough to hold an atmosphere but not so large as to have a crushing gravity. It must orbit in the "goldilocks zone" --- warm enough for liquid water but not so hot as to boil it away. Earth fits those conditions admirably. Mars is just barely within the zone on the cold side while Venus seems to be just outside of it on the hot side.
I understand what you mean, and that's what astronomers mean, but I disagree with such broad conditions being termed "earthlike."
Using what sounds like a "commonsense" term for something that is actually quite distinct from common sense is bad taxonomy.
Scientists ought really to be more closely specific in their terms than that. The commonsense understanding of "Earthlike" would be a condition naturally hospitable to nearly any temperate-zone earth creature.
Mars, for instance, should not be considered "earthlike." They'd be better off creating a scaling system as they do for stars to describe for themselves where such planets would fall on the scale. So call a planet that would be naturally hospitable to nearly any temperate-zone earth creature something like "Class M." Then they could say that "hard surfaced (rocky) planet not a gas giant. It must be large enough to hold an atmosphere but not so large as to have a crushing gravity. It must orbit in the 'goldilocks zone' --- warm enough for liquid water but not so hot as to boil it away" is a planet between classes, say, H to Q.
But using a "commonsense" term for something that actually requires a special understanding of the definition is bad taxonomy.
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