Expositional

[ek-spuh-zish-uh n] /ˌɛk spəˈzɪʃ ən/

noun
1.
a large-scale public exhibition or show, as of art or manufactured products:
an exposition of 19th-century paintings; an automobile exposition.
Synonyms: exhibit, demonstration, display, presentation.
2.
the act of expounding, setting forth, or explaining:
the exposition of a point of view.
3.
writing or speech primarily intended to convey information or to explain; a detailed statement or explanation; explanatory treatise:
The students prepared expositions on familiar essay topics.
Synonyms: elucidation, commentary; critique, interpretation, exegesis, explication.
4.
the act of presenting to view; display:
The singer gave a splendid exposition of vocal talent.
5.
(def 12).
6.
the state of being uncovered, revealed, or otherwise ; exposure.
7.
Music. the first section of a fugue or a sonata form, in which the principal themes normally are introduced.
8.
(in a play, novel, etc.) dialogue, description, etc., that gives the audience or reader the background of the characters and the present situation.
/ˌɛkspəˈzɪʃən/
noun
1.
a systematic, usually written statement about, commentary on, or explanation of a specific subject
2.
the act of expounding or setting forth information or a viewpoint
3.
a large public exhibition, esp of industrial products or arts and crafts
4.
the act of exposing or the state of being exposed
5.
the part of a play, novel, etc, in which the theme and main characters are introduced
6.
(music) the first statement of the subjects or themes of a movement in sonata form or a fugue
7.
(RC Church) the exhibiting of the consecrated Eucharistic Host or a relic for public veneration
n.

late 14c., “explanation, narration,” from Old French esposicion (12c.), from Latin expositionem (nominative expositio) “a setting or showing forth,” noun of action from past participle stem of exponere (see expound).

The meaning “public display” is first recorded 1851 in reference to the Crystal Palace Exposition in London. Abbreviation Expo is first recorded 1963, in reference to planning for the world’s fair held in Montreal in 1967.