Meanwhile Scene

A scene that takes place somewhere else than where the main characters are. Usually used to cut to villains or other plot-important characters to show what they're doing, in order to build up Foreshadowing and drama. Beware of Cryptic Conversations.

Differs from Meanwhile Back At The because the transition only happens for one scene, rather than cutting to another plot thread or viewpoint.

Examples of Meanwhile Scene include:

Film

Parodied in the French film La Cite De La Peur: while the film is set in Cannes, France, it sometimes cuts to Vera Cruz, Mexico, with the obligatory off-voice narration "Meanwhile, in Vera Cruz..." The Vera Cruz scenes have absolutely no relevance to the plot and only show a woman shopping at a grocery store.

Video Games

Last Scenario does this often, usually to what the current villain is doing, or to foreshadow a Man Behind the Man. A Running Gag in Keltena's screencap Let's Play:

Meeeeeaaaaaanwhile...

Exit Fate too, usually with lots of Cryptic Conversations.
Dhux's Scar also does this a lot, usually to Maikas or Halbarad. Lampshaded if you open the game with RPG Maker, where all the Maikas scenes are named "More Maikas", "Even More Maikas", etc., finally culminating in a map named "Nowthisistoomuch".
Each chapter of MARDEK ends with a cutscene involving the members of the Governance de Magi.
A slightly different flavor in the first two installments of Paper Mario, where you actually control the character the scenes revolve around (in both cases Peach) instead of a cutscene. Played straight in Super Paper Mario, with cutscenes of Count Bleck and his minions.
The music that plays during such scenes in Final Fantasy IV is called "Meanwhile, At This Time..." in Japanese or "Somewhere in the World..." in English.
Several cutscenes between the sectors in Jumper Two switch their viewpoint to the Boss' dialouge with his minions.
Radiant Historia occasionally cuts to the villains after a mission is complete.

Theater

In Shakespeare's Twelfth Night Act III scenes 2 & 4 overlap timewise. In scene 2 Sir Toby, Sir Andrew & Fabian have a scene, then Maria comes to get Toby & Fabian to see how ridiculous Malvolio is acting in front of Olivia. In scene 4 Olivia has called Malvolio, he appears and acts ridiculous at her, Maria disappears; then Olivia leaves and Maria reappears with Toby & Fabian.