■ noun
1》 a title or brief explanation appended to an illustration or cartoon.
↘a piece of text appearing on screen as part of a film or broadcast.
2》 Law the heading of a legal document.
■ verb provide with a ~.
Origin
ME (in the sense 'seizing, capture', later 'warrant for arrest' and so 'statement of the authority issuing the warrant'): from L. captio(n-) , from capere 'take, seize'.