Definition
A Latin term of the civil and old English law with three related but distinct operational meanings, each describing a different mode of legal falling or occurrence:
1. To fall into — used to describe entry into a legal condition, status, or obligation.
2. To fall out; to happen; to come to pass — used in a temporal or eventive sense, describing the occurrence of a legally relevant fact or circumstance.
3. To fall upon or under; to become subject or liable to — used to describe the attachment of legal consequence to a person or act. The phrase incidere in legem captures this meaning precisely: to fall into (or under) a law, meaning to incur its penalty or become bound by its operation.
The term appears in civilian sources primarily as a structural verb — it answers the question of how a legal consequence attaches to a fact, person, or situation.
Common Language
Wiktionary (incidere): Latin verb meaning "to cut into," "to fall upon," or "to happen." Used in classical Latin both for physical cutting (as in incision) and for occurrence or befalling.
Webster's 1913: Does not carry a direct entry for incidere as an English word, reflecting its status as an untranslated Latin borrowing in legal contexts.
The gap worth noting: the cutting sense of incidere (the root of English "incision") is the dominant meaning in general classical Latin and ordinary educated usage. In legal contexts, the falling sense — derived from cadere rather than caedere — governs entirely. A researcher encountering incidere in a legal text should resist the instinct toward the cutting meaning and read it as falling upon or becoming subject to.
Common Confusion
Incidere shares a root ambiguity in classical Latin itself: the word can derive from in + caedere (to cut into) or in + cadere (to fall into). These are distinct verbs that happen to produce similar forms. Legal usage draws exclusively from the cadere lineage. The incision meaning (in + caedere) is medically and classically prominent but legally irrelevant. Historical legal dictionaries — Black's, Burrill — confirm uniformly that the cadere derivation governs.
Separate from this root confusion, incidere should not be conflated with incidere in legem as a standalone phrase. The full phrase carries the specific technical meaning of incurring a legal penalty; the bare verb incidere is more general, covering occurrence and the attachment of any legal consequence, not only punitive ones.
Why It Matters in Research
Incidere is a functional verb in civilian and early English legal texts, not a term of art with a standalone doctrine. Researchers are most likely to encounter it in two contexts:
First, in translated or glossed civil law materials where the word anchors a description of how liability or obligation attaches. The phrase incidere in legem is the most common fixed expression and appears in Brissonius and in Roman law sources dealing with statutory penalties.
Second, as a building block for derivative terms. The Law Mind corpus contains entries for INCIDENT and INCIDENTAL, both of which trace their operative legal logic to this Latin root. Understanding incidere clarifies why an incident right is one that falls upon or attaches to a principal thing — not one that merely accompanies it by convention. The falling metaphor is structural, not decorative.
Trap for historical researchers: Black's 1st edition indexes incidere under the broader INCIDENT headnote, meaning the term may not surface as a standalone entry in older digests. Burrill isolates it more cleanly. When reading early equity or common law treatises that use incidere or its anglicized forms, confirm which of the three meanings applies — occurrence, status entry, or liability attachment — before drawing interpretive conclusions.
The related civil law term INCILE (a trench, so named because it is cut — incidatur — into stone or earth) appears in Black's 2nd edition immediately following incidere. This adjacency is an artifact of alphabetical arrangement and the shared root, not legal relationship. Do not treat INCILE as a legal consequence of incidere; they share a root but serve entirely different doctrinal functions.
Historical Dictionary Support
Black's 1st and 2nd editions give nearly identical entries, both citing Calvin (Lexicon Iuridicum) for the falling-into and happening senses and Brissonius (De Verborum Significatione) for the liability-attachment sense. This citation pattern reflects the standard civilian source chain and gives the entry reasonable authority.
Burrill adds the etymological derivation explicitly — in + cadere — which is more precise than Black's presentation and helpful for researchers navigating the caedere/cadere confusion. Burrill also preserves the Calv. Lex. citations for both core senses.
What the historical dictionaries do not do: none of them discuss incidere as it functions in specific Roman law titles or trace how the term migrated into English equity practice. The entries are definitional glosses, not doctrinal treatments. For the operative use of incidere in penalty contexts, the Digest (particularly titles dealing with statutory liability) would be the necessary next source.