Hostus was a Roman champion who fell in battle against the Sabines under Titus Tatius in the earliest years of the city.
As with other praenomina, the name may have been more widely used by the plebeians and in the countryside; but writing in the 1st century BC, Marcus Terentius Varro described it as an archaic praenomen, no longer in general use.
Chase proposed that Hostus might be derived from hostis, "stranger, foe", but this meaning seems difficult to explain.
is suggested by the Etruscan feminine praenomen Hasti, which may originally have been a variant of Fasti, in which the initial consonant has been "worn down".
Fasti is believed to be the Etruscan cognate of the Latin name Fausta, in which case it is conceivable that the same process resulted in the development of Hostus from the praenomen Faustus.