a long speech by one actor in a play or movie, or as part of a theatrical or broadcast program

The answer is monologue.

Explanation:

A monologue is a long speech by one actor in a play or movie, or as part of a theatrical or broadcast program. MONO here means one.

In theatre, a monologue is a speech usually presented by a single character. It is most often to express their mental thoughts aloud often presented as though, the character is deep in thought to the point of voicing them or simply having a conversation with himself.

A monologue sometimes can also be used to directly address another character or even the audience.

this doesnt make any sense imao