Wallowing (or "wallering") refers to an actor deeply immersing themselves in an emotion, character state, or moment to an extreme, often self-indulgent degree. 

• It often describes an actor overacting or "hamming it up" while portraying intense, negative emotions like self-pity, grief, or despair, taking a moment of drama to a theatrical extreme.
• It is closely related to the concept of "chewing the scenery," where an actor is overly dramatic or larger-than-life in a scene
• It can also refer to a deliberate, slow, and often clumsy physical movement on stage, emphasizing a state of being completely consumed by a situation.
• It's sometimes used to mean an action with a specific, often critical, attitude—a way of "taking to the bed in despair" to ensure the audience or other characters notice the distress.
• While it can sometimes refer to a positive, luxurious indulgence in a scene, in the context of acting, it is most often used to criticize a performance that lacks subtlety or is intentionally, over-the-top unhappy.

In opera and musical theatre, a “wandelprobe” is a musical rehearsal in which the actors and singers are free to move around on the stage while the band or orchestra plays. They still have to sing the parts they are assigned while moving.

The word "wandelprobe" comes from German and technically means "convertable trial," but in the theatre it translates as a "walking rehearsal." This sets it apart from a seated  rehearsal or "sitzprobe," where the focus is on giving the singers an opportunity to hear the full orchestra, and adjust their performance accordingly. It's sometimes referred to in the U.S. as a "wanderprobe," mostly due to a misunderstanding (or mispronunciation) of "wandel."

The movement in a “wandelprobe” isn't free-range wandering. The performers have to move to the approximate blocking for the production, if not the exact blocking, with the music’s tempo in mind.  There may be stops in order to work with the orchestra or band and the actors or singers in order to figure out how movements go together with the music.

A wandelprobe is usually held before tech starts and there usually are no lighting cues. However, everything is up to the decisions of the director and conductor. A wandelprobe (or even more than one wandelprobe) takes place before the first full dress rehearsal. 

Person who supervises the dressers, and wardrobe maintenance. 

An even, overall illumination that bathes a large area of the stage. Also, a specialized lighting instrument designed for that purpose.

Person who acquires and styles wigs and hairpieces, and often is in charge of maintaining them through the run of a production.