The Unconscious World of Dream
(1) By virtue of its sexual associations, dancing may represent a coming together - courtship - of the masculine (animus) and feminine (anima) side of one's nature. See anima - animus
(2) Joining a dance probably means relating cooperatively with the other person or group. What does that person or group symbolize? It may be some part of you: your hidden self, with its mulitude of emotions, instinctive impulses, ideas, ideals, beliefs/prejudices, attitudes, ambitions, etc.
(3) Perhaps it is the 'dance of life'. Participating/not participating in the dance would then mean relating harmoniously with Nature (or your unconscious)/being out of step with it. (Dancing clumsily may signify that you are 'out of step'.)
(4) If the dance is a frenzied solo performance, it may represent some kind of 'possession', indicating that some psychic element (unconscious)is threatening to take you over. If this is the case, you need to identify the causes of any comulsive behaviour you observe in yourself; and then to come to terms with it - which will usually mean either making space in your life for some hitherto repressed part of you; or getting rid of (repressed)guilt-feelings; or both.
Dancing may be a sexual symbol, representing sexual intercourse.
Reference: Eric Ackroyd
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