Virbius was a Roman god associated with the worship of Diana. When Diana was identified with Artemis, Virbius was identified with Hippolytus, and it was explained that he had been raised from the dead by Asclepius and brought to Rome by Artemis.
In view of this 'rebirth', many writers have not been able to resist the temptation to derive his name from vir bis, 'a man for a second time'! Almost as unlikely is a link that has been proposed with verbena, in spite of the religious associations of this herb. More likely is a derivation from something like hiros, 'holy' and bios, 'life', with the 'h' becoming 'b' as in the Hestia and Vesta doublet.