Interiectus

Interiectus is a Latin term functioning as an adjective and the perfect passive participle of intericio, meaning “thrown between” or “inserted.” The word combines inter- “between” with iacio “to throw,” conveying the sense of something placed between other elements, rather than forming part of their essential structure.

In classical Latin, interiectus describes words, phrases, or clauses that have been inserted into a discourse or sentence—interpolations that expand or modify the original meaning but are not strictly necessary to the syntax. The related noun interiectio denotes an interjection, and interiectus is often discussed in studies of textual layering and rhetorical technique, where the focus is on material added to a text rather than on its core composition.

In manuscript studies and textual criticism, interiectus is used to refer to insertions in a base text, such as glosses, marginal notes, or editorial interpolations that were added after the initial composition. Identifying interiectus helps scholars distinguish the author’s original wording from later additions, a process central to attempts to recover a text’s initial form.

Today, the Latin term is primarily of historical and philological interest. In English-language scholarship, the concept is generally described using interpolation or interpolated material rather than the Latin word itself. The term remains relevant for discussions of how texts acquire additional layers through later insertions.