regula

Regula is a Latin noun that means rule, guideline, or standard. In Latin, regula can refer to a straight edge or measure, and the term has entered many languages as a loanword used to designate a norm, principle, or method. The Latin plural regulae is sometimes found in scholarly or historical texts.

In religious and monastic contexts, regula denotes a set of rules governing communal life, prayer, labor, and discipline. Monastic communities often followed a specific regula, a structured program that shaped daily routines and spiritual practice. The most famous example is the Regula Benedicti, known in English as the Benedictine Rule, which influenced many Western monastic orders and their organizational structure.

In theology and law, regula is used to indicate established principles or standards used to interpret doctrine or practice. Phrases such as regula fidei (rule of faith) and regulae iuris (rules of law) appear in medieval and canonical writings and continue to be referenced in scholarly discussions of normative principles.

In science and mathematics, regula appears in Latin titles and terms that describe procedural rules. A well-known example is Regula falsi, the false-position method for locating zeros of a function. The word is often encountered in historical or technical literature to denote a standard method or guideline within a discipline.

In modern usage, regula survives primarily as a formal or historical term rather than a living everyday word, appearing in scholarly, liturgical, or legal contexts. Regula is also used as a feminine given name in some German-speaking regions.