Learn how to say Captionist correctly in English with this tutorial pronunciation video.
Oxford dictionary definition of the word caption:
a title or brief explanation accompanying an illustration, cartoon, or poster:
he designed a series of posters with the caption: ‘No One is Innocent’
a piece of text appearing on a cinema or television screen as part of a film or broadcast:
the programme has a closing caption thanking the university for its cooperation
Law the heading of a legal document.
provide (an illustration) with a title or explanation:
[with two objects]:
the photograph was captioned ‘Three little maids’
late Middle English (in the sense ‘seizing, capture’): from Latin captio(n-), from capere ‘take, seize’. Early senses ‘arrest’ and ‘warrant for arrest’ gave rise to ‘statement of where, when, and by whose authority a warrant was issued’ (late 17th century): this was usually appended to a legal document, hence the sense ‘heading or accompanying wording’ (late 18th century)