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(virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts; many are pathogenic; a piece of nucleic acid (DNA or RNA) wrapped in a thin coat of protein

a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer; "a true virus cannot spread to another computer without human assistance"

a harmful or corrupting agency; "bigotry is a virus that must not be allowed to spread"; "the virus of jealousy is latent in everyone"

The special contagion, inappreciable to the senses and acting in exceedingly minute quantities, by which a disease is introduced into the organism and maintained there.

Fig.: Any morbid corrupting quality in intellectual or moral conditions; something that poisons the mind or the soul; as, the virus of obscene books.

Contagious or poisonous matter, as of specific ulcers, the bite of snakes, etc.; - applied to organic poisons.

The special contagion, inappreciable to the senses and acting in exceedingly minute quantities, by which a disease is introduced into the organism and maintained there.

Fig.: Any morbid corrupting quality in intellectual or moral conditions; something that poisons the mind or the soul; as, the virus of obscene books.

Contagious or poisonous matter, as of specific ulcers, the bite of snakes, etc.; - applied to organic poisons.

Minute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells.

Poison; the poisonous matter produced by disease, containing the germs that cause the disease; hence, anything that poisons the mind or soul, as treachery.

1. Contagium, the specific poison of an infectious disease. 2. Vaccine lymph.

Substance formed in an infectious disease.

VIRULENCE.

A slimy liquid: contagious or poisonous matter (as of ulcers, etc.): the poison which causes infection: any foul, hurtful matter.

VIRULENCE.

A morbid poison that is the means of communioating infectious disease.

Contagious matter from ulcers, &c.; poison.

Active or contagious matter of an ulcer, pustule, &c.; a poisonous principle or matter which engenders a zymotic disease.

The contagious or poisonous matter of an ulcer or a pustule, &c.; any foul hurtful matter.

An animal poison, especially one produced by, and capable of transmitting, a disease.

Any morbific agent which, when brought into contact with animal tissue, disseminates itself so as to affect the vitality of the parts on which it acts and in many cases that of the entire organism.

n. [Latin] Contagious or poisonous matter, as of specific ulcers, the bite of snakes, ;—the special contagion of a disease;—hence, the spirit, aim, or drift of any tiling injurious of a moral nature.