illustratory

Illustratory is an adjective used to describe something that serves to illustrate a point or concept; it denotes a function of providing illustration, example, or clarification. In practice, illustratory material can include diagrams, captions, or examples that help explain a topic. The term is a near-synonym of illustrative, though illustrative is more prevalent in contemporary English.

Etymology and linguistic notes: the word derives from the Latin illustratus, from illuminare “to illuminate,” combined with the English suffix -ory. Its formation mirrors other -atory adjectives that express function or purpose. In English usage, illustratory has appeared since early modern times but has remained comparatively rare.

Usage and stylistic considerations: illustratory is relatively uncommon today and may sound formal or archaic in ordinary prose. It is most likely to appear in scholarly, historical, or technical writing, where a precise emphasis on the illustrative function is desired. In most modern contexts, authors will prefer illustrative, explanatory, or demonstrative as more natural alternatives. When choosing between terms, readers should consider whether the priority is the act of illustrating (illustratory) or the result of illustration (illustrative).

See also: illustration; illustrative; explanatory; diagram; visual aids.