Definitions of Roman legal terms
This page contains a noninclusive list of legal terms used in ancient Rome.
In Roman law during the Republic, calumnia was the willful bringing of a false accusation, that is, malicious prosecution. 
In ancient Roman culture, infamia (in-, "not," and fama, "reputation") was a loss of legal or social standing. As a technical term of Roman law, infamia was an official exclusion from the legal protections enjoyed by a Roman citizen, as imposed by a censor or praetor. More generally, especially during the Republic and Principate, infamia was informal damage to one's esteem or reputation. A person who suffered infamia was an infamis (plural infames).
Infamia was an "inescapable consequence" for certain professionals, including prostitutes and pimps, entertainers such as actors and dancers, and gladiators. Infames could not, for instance, provide testimony in a court of law. They were liable to corporal punishment, which was usually reserved for slaves. The infamia of entertainers did not exclude them from socializing among the Roman elite, and entertainers who were "stars," both men and women, sometimes became the lovers of high-profile figures.
A passive homosexual who was "outed" might also be subject to social infamia, though if he was a citizen he might retain his legal standing.
Ingenui or ingenuitas (singular ingenuus), was a legal term of ancient Rome indicating those freemen who were born free, as distinct from, for example, freedmen, who were freemen who had once been slaves.
Incestum is an act that violates religious purity. (sacrilege)
1 Sexual intercourse between a man and an unmarried woman other than one in slavery or concubinage
2 Illicit intercourse contrary to morality
3 Unchastity of a woman 
- Mary Beard, J.A. North, and S.R.F. Price, Religions of Rome: A History (Cambridge University Press, 1998), vol. 1, p. 238.
- Thomas A.J. McGinn, Prostitution, Sexuality and the Law in Ancient Rome (Oxford University Press, 1998), p. 65ff.
- Catharine Edwards, "Unspeakable Professions: Public Performance and Prostitution in Ancient Rome," in Roman Sexualities (Princeton University Press, 1997, p. 67.
- Edwards, "Unspeakable Professions," p. 73.
- Amy Richlin, "Not before Homosexuality: The Materiality of the cinaedus and the Roman Law against Love between Men," Journal of the History of Sexuality 3.4 (1993), pp. 550–551, 555ff.; Edwards, "Unspeakable Professions," p. 68.
- Long, George (1870). "Ingenui". in Smith, William. Dictionary of Greek and Roman Antiquities. Boston: Little, Brown and Company. pp. 637