virus

As a noun virus

is virus.

As a proper noun key is

.

As nouns the difference between animals and virus

is that animals is while virus is virus.

As nouns the difference between virus and null

is that virus is virus while null is zero, nil; the cardinal number before einn.

As an adjective human

is (label) classical (of or pertaining to the classical - latin, greek - languages, literature, history and philosophy).

As a noun virus is

virus.

As nouns the difference between virus and illness

is that virus is virus while illness is (countable) an instance of a disease or poor health.

As nouns the difference between virus and infection

is that virus is venom, as produced by a poisonous animal etc while infection is the act or process of infecting.

As nouns the difference between sputnik and virus

is that sputnik is any of a series of soviet unmanned space satellites, especially the first one in 1957 while virus is virus.

As nouns the difference between prokaryote and virus

is that prokaryote is an organism whose cell (or cells) are characterized by the absence of a nucleus or any other membrane-bound organelles while virus is virus.

As nouns the difference between ghost and virus

is that ghost is (rare) the spirit; the soul of man while virus is virus.

As a verb ghost

is (obsolete|transitive) to haunt; to appear to in the form of an apparition.

As nouns the difference between virus and bag

is that virus is virus while bag is a flexible container made of cloth, paper, plastic, etc.

As a verb bag is

to put into a bag.