I. ˈsəb+|- noun
Etymology: sub- + title
1.
a. : a secondary title
in Uncle Tom's Cabin, or Life Among the Lowly the subtitle is Life Among the Lowly
— called also alternative title
b. : an explanatory title
in The Behavior of Organisms; an Experimental Analysis the subtitle is an Experimental Analysis
2.
a. : a printed translation of foreign language dialogue appearing near the bottom of the screen of a motion picture
b. : a printed statement or fragment of dialogue appearing between the scenes of a silent motion picture
II. transitive verb
: to give a subtitle to