The Collaborative International Dictionary of English v.0.48:

Penates \Pe*na"tes\, n. pl. [L.] (Rom. Antiq.)
   The household gods of the ancient Romans. They presided over
   the home and the family hearth. See Lar.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "penates":
   Hestia, Vesta, ancestral spirits, angel, attendant godling,
   control, daemon, demon, fairy godmother, familiar, familiar spirit,
   genius, genius domus, genius loci, good angel, good genius,
   guardian, guardian angel, guardian spirit, guide, household gods,
   invisible helper, lares and penates, lares compitales,
   lares familiaris, lares permarini, lares praestites, lares viales,
   manes, ministering angel, numen, special providence, totem,
   tutelar god, tutelary