Earth, world, universe, cosmos, macrocosm are comparable when they mean the entire area or extent of space in which man thinks of himself and of his fellow men as living and acting.
Earth applies, however, only to part of what he knows by sight or by faith to exist; the term usually suggests a distinction between the sphere or globe called astronomically the earth, which he knows to be composed of land and water, and the bodies which he sees in the heavens.
It may imply a distinction from heaven and hell.
World is a far less definite term than earth. When applied to a physical entity, it may denote all that illimitable area which to man’s senses, at least, includes not only the earth and other planets but all the space surrounding the earth and all the bodies contained within it.
To persons who accept the account of creation in Genesis the term denotes the entire system that was brought into being by the word of God.
The term, nevertheless, is usually used as equivalent to earth, the globe.
As applied to an immaterial entity, world may imply the sum total of all the inhabitants of earth and of their interests and concerns or that section or part of this larger world which comes within the knowledge of the individual or the section or part of the larger world which is devoted to secular, as distinct from religious or spiritual, concerns.
Universe, in its most precise sense, denotes the entire system of created things or of physical phenomena, regarded as a unit both in its organization and in its operation.
Universe, however, is also used in reference to an entire system of phenomenal things as that system appears to the limited vision of the typical man or of the individual.
Cosmos, because of its opposition to chaos, carries a stronger implication of order and harmony in operation than universe, which it otherwise closely resembles in meaning.
Macrocosm applies to the universe thought of as a great whole characterized by perfect organic unity exhibited elsewhere only in the small whole, the individual man or microcosm.