Prelap

Prelap is a screenwriting term that means the dialogue from the next scene precedes the cut, and the beginning of the dialogue is heard in the outgoing scene. As an example:

ADRIAN (V.O., PRELAP)
Peter?  Peter, where are you?

EXT. THE WOODS – DAY

Adrian is out looking for Peter.  
We see him wander around in the small forest.

ADRIAN
Peter?  Hello?  Are you there?

In this example, Adrian's voice precedes the scene out in the woods. The "V.O." means "Voice Over" and the "PRELAP" indicates that Adrian's dialogue should be heard before the next scene begins. Adrian, in this example, might not even be in the scene the other characters are in when the prelap occurs. ("O.S." or "Off Screen" would not be appropriate as the term should only be used for characters unseen but on set.)

Prelaps can be of sound or dialogue, or anything non-visual, since a visual would indicate a direct cut to a new scene.

Film editing

Concept

Choreography
Synchronization
Attentional control
Master shot
Parallel cut

Technique

Clues
Cutaway
Eyeline match
Points of view
Multiple exposure
Optical illusion
Split screen
Transition

Insertion	Dialogue Match cut Long shot Insert
Timelapsing	Cut Jump cut Axial cut Wipe Dissolve Slow motion Prelap
Other	Fast cutting Invisible cut Montage Supercut