Lares were the Roman household gods: each Roman house had its Lar who was honoured together with the family's Penates and Vesta. These gods seem to have originated as the deified spirits of dead ancestors.
Their name seems to be of Tuscan (or perhaps Sabine) origin, with possibly a meaning 'lord' (which English word, in spite of the resemblance, could not be related to them). Eric Partridge, however, relates the name to Latin larva or larua, 'ghost', 'mask', and thus to English 'larva', which resembles a mask.