Flail dream meaning is explained below using 2 different sources. Each interpretation is shown with its source.

Interpretation 1 — Pamela Ball

1- Any instrument used to beat us in dreams is a recognition that someone has power over us, and can use force rather than giving us the power to act for ourselves.

2- The flail would reinforce our ideas about authority. In older times the Jester would use a pig’s bladder to flail the king to remind him of his humility.

3- A llail also sometimes represents spiritual supremacy and Supreme power which may be available to us.

Source: Ten Thousand Dream Dictionary Author: Pamela Ball

Interpretation 2 — Dream Explanations - Anonymous

Dreams of flailing are about processing your uncentered, unfocussed, feelings; you are releasing that you don’t know your rightful place. This dream could also be a call for you to stop running around and drop into your center via a meditation and/or your spiritual practice. Your dream is telling you not to move until you are moved by your higher guidance.
Source: Strangest Dream Explanations Author: Dream Explanations - Anonymous