So these are copy pasted from Wikipedia, but I figured it was a good thing to have these in a set location people could find easily. There are terms missing in this series, but it at least will be a start.
The verb abominari (“to avert an omen”, from ab-, “away, off,” and ominari, “to pronounce on an omen”) was a term of augury for an action that rejects or averts an unfavourable omen indicated by a signum, “sign”. The noun is abominatio, from which English “abomination” derives. At the taking of formally solicited auspices (auspicia impetrativa), the observer was required to acknowledge any potentially bad sign occurring within the templum he was observing, regardless of the interpretation. He might, however, take certain actions in order to ignore the signa, including avoiding the sight of them, and interpreting them as favourable. The latter tactic required promptness, wit and skill based on discipline and learning. Thus the omen had no validity apart from the observation of it.
The aedes was the dwelling place of a god. It was thus a structure that housed the deity’s image, distinguished from the templum or sacred district. Aedes is one of several Latin words that can be translated as “shrine” or “temple”; see also delubrum and fanum. For instance, the Temple of Vesta, as it is called in English, was in Latin an aedes. See also the diminutive aedicula, a small shrine.
In his work On Architecture, Vitruvius always uses the word templum in the technical sense of a space defined through augury, with aedes the usual word for the building itself. The design of a deity’s aedes, he writes, should be appropriate to the characteristics of the deity. For a celestial deity such as Jupiter, Coelus, Sol or Luna, the building should be open to the sky; an aedes for a god embodying virtus (valour), such as Minerva, Mars, or Hercules, should be Doric and without frills; the Corinthian order is suited for goddesses such as Venus, Flora, Proserpina and the Lymphae; and the Ionic is a middle ground between the two for Juno, Diana, and Father Liber. Thus in theory, though not always in practice, architectural aesthetics had a theological dimension.
The word aedilis (aedile), a public official, is related by etymology; among the duties of the aediles was the overseeing of public works, including the building and maintenance of temples. The temple (aedes) of Flora, for instance, was built in 241 BC by two aediles acting on Sibylline oracles. The plebeian aediles had their headquarters at the aedes of Ceres.
In religious usage, ager (territory, country, land, region) was terrestrial space defined for the purposes of augury in relation to auspicia. There were five kinds of ager: Romanus, Gabinus, peregrinus, hosticus and incertus. The ager Romanus originally included the urban space outside the pomerium and the surrounding countryside. According to Varro, the ager Gabinus pertained to the special circumstances of the oppidum of Gabii, which was the first to sign a sacred treaty (pax) with Rome. The ager peregrinus was other territory that had been brought under treaty (pacatus). Ager hosticus meant foreign territory; incertus, “uncertain” or “undetermined,” that is, not falling into one of the four defined categories. The powers and actions of magistrates were based on and constrained by the nature of the ager on which they stood, and ager in more general usage meant a territory as defined legally or politically. The ager Romanus could not be extended outside Italy (terra Italia).
The focal point of sacrifice was the altar (ara, plural arae). Most altars throughout the city of Rome and in the countryside would have been simple, open-air structures; they may have been located within a sacred precinct (templum), but often without an aedes housing a cult image. An altar that received food offerings might also be called a mensa, “table.”
Perhaps the best-known Roman altar is the elaborate and Greek-influenced Ara Pacis, which has been called “the most representative work of Augustan art.” Other major public altars included the Ara Maxima.
A tree (arbor) was categorized as felix if it was under the protection of the heavenly gods (di superi). The adjective felix here means not only literally “fruitful” but more broadly “auspicious”. Macrobius lists arbores felices (plural) as the oak (four species thereof), the birch, the hazelnut, the sorbus, the white fig, the pear, the apple, the grape, the plum, the cornus and the lotus. The oak was sacred to Jupiter, and twigs of oak were used by the Vestals to ignite the sacred fire in March every year. Also among the felices were the olive tree, a twig of which was affixed to the hat of the Flamen Dialis, and the laurel and the poplar, which crowned the Salian priests.
Arbores infelices were those under the protection of chthonic gods or those gods who had the power of turning away misfortune (avertentium). As listed by Tarquitius Priscus in his lost ostentarium on trees, these were buckthorn, red cornel, fern, black fig, “those that bear a black berry and black fruit,” holly, woodland pear, butcher’s broom, briar, and brambles.”
The verb attrectare (“to touch, handle, lay hands on”) referred in specialized religious usage to touching sacred objects while performing cultic actions. Attrectare had a positive meaning only in reference to the actions of the sacerdotes populi Romani (“priests of the Roman people”). It had the negative meaning of “contaminate” (= contaminare) or pollute when referring to the handling of sacred objects by those not authorized, ordained, or ritually purified.
An augur (Latin plural augures) was an official and priest who solicited and interpreted the will of the gods regarding a proposed action. The augur ritually defined a templum, or sacred space, declared the purpose of his consultation, offered sacrifice, and observed the signs that were sent in return, particularly the actions and flight of birds. If the augur received unfavourable signs, he could suspend, postpone or cancel the undertaking (obnuntiatio). “Taking the auspices” was an important part of all major official business, including inaugurations, senatorial debates, legislation, elections and war, and was held to be an ancient prerogative of Regal and patrician magistrates. Under the Republic, this right was extended to other magistrates. After 300 BC, plebeians could become augurs.
The solicitation of formal auspices required the marking out of ritual space (auguraculum) from within which the augurs observed the templum, including the construction of an augural tent or hut (tabernaculum). There were three such sites in Rome: on the citadel (arx), on the Quirinal Hill, and on the Palatine Hill. Festus said that originally the auguraculum was in fact the arx. It faced east, situating the north on the augur’s left or lucky side. A magistrate who was serving as a military commander also took daily auspices, and thus a part of camp-building while on campaign was the creation of a tabernaculum augurale. This augural tent was the center of religious and legal proceedings within the camp.
Augurium (plural auguria) is an abstract noun that pertains to the augur. It seems to mean variously: the “sacral investiture” of the augur; the ritual acts and actions of the augurs; augural law (ius augurale); and recorded signs whose meaning had already been established. The word is rooted in the IE stem *aug-, “to increase,” and possibly an archaic Latin neuter noun *augus, meaning “that which is full of mystic force.” As the sign that manifests the divine will, the augurium for a magistrate was valid for a year; a priest’s, for his lifetime; for a temple, it was perpetual.
The distinction between augurium and auspicium is often unclear. Auspicia is the observation of birds as signs of divine will, a practice held to have been established by Romulus, first king of Rome, while the institution of augury was attributed to his successor Numa. For Servius, an augurium is the same thing as auspicia impetrativa, a body of signs sought through prescribed ritual means. Some scholars think auspicia would belong more broadly to the magistracies and the patres while the augurium would be limited to the rex sacrorum and the major priesthoods.
Ancient sources record three auguria: the augurium salutis in which every year the gods were asked whether it was fas (permissible, right) to ask for the safety of the Roman people (August 5); the augurium canarium, a dog sacrifice to promote the maturation of grain crops, held in the presence of the pontiffs as well as the augurs; and the vernisera auguria mentioned by Festus, which should have been a springtime propitiary rite held at the time of the harvest (auguria messalia).
The auspex, plural auspices, is a diviner who reads omens from the observed flight of birds (avi-, from avis, “bird”, with -spex, “observer”, from spicere). See auspicia following and auspice.
The auspicia (au- = avis, “bird”; -spic-, “watch”) were originally signs derived from observing the flight of birds within the templum of the sky. Auspices are taken by an augur. Originally they were the prerogative of the patricians, but the college of augurs was opened to plebeians in 300 BC. Only magistrates were in possession of the auspicia publica, with the right and duty to take the auspices pertaining to the Roman state. Favorable auspices marked a time or location as auspicious, and were required for important ceremonies or events, including elections, military campaigns and pitched battles.
According to Festus, there were five kinds of auspicia to which augurs paid heed: ex caelo, celestial signs such as thunder and lightning; ex avibus, signs offered by birds; ex tripudiis, signs produced by the actions of certain sacred chickens; ex quadrupedibus, signs from the behavior of four-legged animals; and ex diris, threatening portents. In official state augury at Rome, only the auspicia ex caelo and ex avibus were employed.
The taking of the auspices required ritual silence (silentium). Watching for auspices was called spectio or servare de caelo. The appearance of expected signs resulted in nuntiatio, or if they were unfavourable obnuntiatio. If unfavourable auspices were observed, the business at hand was stopped by the official observer, who declared alio die (“on another day”).
The practice of observing bird omens was common to many ancient peoples predating and contemporaneous with Rome, including the Greeks, Celts, and Germans.
Auspicia impetrativa were signs that were solicited under highly regulated ritual conditions (see spectio and servare de caelo) within the templum. The type of auspices required for convening public assemblies were impetrativa, and magistrates had the “right and duty” to seek these omens actively. These auspices could only be sought from an auguraculum, a ritually constructed augural tent or “tabernacle” (tabernaculum). Contrast auspicia oblativa.
The right of observing the “greater auspices” was conferred on a Roman magistrate holding imperium, perhaps by a Lex curiata de imperio, although scholars are not agreed on the finer points of law. A censor had auspicia maxima. It is also thought that the flamines maiores were distinguished from the minores by their right to take the auspicia maiora; see Flamen.
Signs that occurred without deliberately being sought through formal augural procedure were auspicia oblativa. These unsolicited signs were regarded as sent by a deity or deities to express either approval or disapproval for a particular undertaking. The prodigy (prodigium) was one form of unfavourable oblativa. Contrast auspicia impetrativa.
Private and domestic religion was linked to divine signs as state religion was. It was customary in patrician families to take the auspices for any matter of consequence such as marriages, travel, and important business. The scant information about auspicia privata in ancient authors suggests that the taking of private auspices was not different in essence from that of public auspices: absolute silence was required, and the person taking the auspices could ignore unfavourable or disruptive events by feigning not to have perceived them. In matters pertaining to the family or individual, both lightning and exta (entrails) might yield signs for privati, private citizens not authorized to take official auspices. Among his other duties, the Pontifex Maximus advised privati as well as the official priests about prodigies and their forestalling.
In pontifical usage, the verb averruncare, “to avert,” denotes a ritual action aimed at averting a misfortune intimated by an omen. Bad omens (portentaque prodigiaque mala) are to be burnt, using trees that are in the tutelage of underworld or “averting” gods (see arbores infelices above). Varro says that the god who presides over the action of averting is Averruncus.