Priestess presiding over a sacrifice (Roman, from near the Sanctuary of Diana at Nemi, 200 CE)
Relief on a marble altar containing images relating to the goddess Diana. An attendant brings the bull to the altar while another stands behind the altar holding ritual objects for the ceremony. The veiled priestess probably held a patera in her left hand, about to ritually purify the sacrificial bull with a libation.
image: VROMA, a virtual community for teaching and learning classics
The Latin word mola* meant, literally, millstone, and by extension ground-up spelt meal, which, mixed with salt (hence the term mola salsa, salted meal), was used as part of every sacrifice, where it was sprinkled on the head of the victim before the actual slaughter took place.
In De verborum significatione (On the meaning of words), compiled in the 2nd century of the Common Era, the Roman grammarian Sextus Pompeius Festus thus defined mola:
vocatur etiam far tostum et sale sparsum, quod eo molito hostiae asperguntur
Spelt parched and sprinkled with salt is so called too, because when it has been ground victims are sprinkled with it.
Therefore, mola is the origin of the verb immolare, meaning, literally, to sprinkle (a victim) with sacrificial meal, hence to sacrifice, to immolate. In the above-mentioned work, Festus gave this definition:
immolare est mola, id est farre molito et sale, hostiam perspersam sacrare
To immolate is to consecrate the victim which has been sprinkled with mola, that is, ground spelt and salt.
In the eighth Eclogue, Virgil used sparge molam, scatter mola. In the commentary on this Eclogue, the Roman grammarian Maurus Servius Honoratus (floruit late 4th-early 5th centuries of the Common Era) described the making of the sacred substance mola salsa:
‘sparge molam’ far et salem. hoc nomen de sacris tractum est: far enim pium, id est mola casta, salsa – utrumque enim idem significat – ita fit. virgines Vestales tres maximae ex nonis Maiis ad pridie idus Maias alternis diebus spicas adoreas in corbibus messuariis ponunt easque spicas ipsae virgines torrent, pinsunt, molunt atque ita molitam condunt. ex eo farre virgines ter in anno molam faciunt, Lupercalibus, Vestalibus, idibus Septembribus, adiecto sale cocto et sale duro.
“Scatter mola”. Spelt and salt. This name was taken from the sacred rites: for holy spelt, that is, pure salted mola – for both signify the same thing – is made thus: the three senior Vestal Virgins from the 7th to the 14th of May on every other day place ears of spelt in reapers’ baskets and the Virgins themselves dry, crush and grind these ears, and then store the meal. From this spelt the Virgins three times a year make mola, during the festivals of Lupercus and of Vesta and on the Ides of September, when boiled salt and hard salt have been added. (from The Vestal Virgins’ Ritual Function in Roman Religion (Classica et Mediaevalia –1999), by Robin Lorsch Wildfang)
The vestal virgins were the priestesses (originally four, subsequently six in number) who had charge of the sacred fire in the temple of Vesta at Rome. Vesta was a Roman female divinity, the daughter of Saturn, goddess of the hearth and household. The name Vesta answered to the Greek Ἑστία (= Hestía), identical with ἑστία (= hestía), hearth, house, household.
* The Latin noun mola is cognate with ancient Greek μύλη, μύλος (= múlē, múlos), mill, millstone, and with English meal, German Mehl, Dutch meel, Danish mel and Swedish mjöl, denoting the edible part of a grain or pulse ground to powder.
The Russian blin, pancake, is probably also a cognate (its plural, blini, has been adopted in English in the sense of pancakes made of buckwheat flour and yeast).
The Portuguese, Spanish, Italian and French feminine nouns mó, muela, mola and meule, meaning millstone, are from Latin mola.