The definition of "earth-like" in this context is almost absurdly broad: roughly it means: a rocky-metallic planet, around Earth mass (maybe 0.5 to 1.5 or so?),

The definition of "earth-like" in this context is almost absurdly broad: roughly it means: a rocky-metallic planet, around Earth mass (maybe 0.5 to 1.5 or so?), and in an orbit that might support liquid water -- not has water, just water would be liquid under some circumstances if it were there. So: - no atmosphere? no problem - no water? no problem - average temperature 40c? fine - 4c? Yup I think both Venus and Mars qualify (barely). All to say, when someone says a planet is "Earth-like" that doesn't mean we should get out our picnic baskets.