Ablution / washing
Psychological (Freud)
Ritual washing in a dream may express the deep wish to be freed from guilt, shame, or repressed impulses and to make a fresh psychological start. It often mirrors a need for purity and atonement, in which the conscience strives for relief and a clear inner state.
Oriental reading
In the Oriental-Islamic tradition, ritual washing in a dream is a sign of repentance, the forgiveness of sins, and release from worries. According to Ibn Sirin, especially when performed completely, it promises the fulfillment of wishes, recovery, and a blessed new beginning in one's affairs.
Spiritual
Dream interpretation is for self-reflection and entertainment — it is not a medical or psychological diagnosis.