Yes, virus is a Scrabble word!

Noun

1. (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

2. A harmful or corrupting agency

3. A software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer