Virus is the only neuter second declension Latin noun in -us (as opposed to -um). It means "poison" in Latin. I assume this was all meant tongue-in-cheek, but i

Virus is the only neuter second declension Latin noun in -us (as opposed to -um). It means "poison" in Latin. I assume this was all meant tongue-in-cheek, but in case anyone is curious, the Latin plural is not virodes. All of this is recalled from my high school Latin, which was a long time ago.