The meaning of seeing or using a cipher in your dream is that you interiorize and not let others to approach you. Consider the digits combination for additional interpretation. The meaning of dreaming that you forgot the cipher combination indicates that you are reticent in fully express yourself. Something keeps you, pulls you back. On the other hand, the dream's interpretation might be related to a date or an appointment that you missed.
You may look in dreams interpretation for other symbols :
Circle : Seeing a circle in your dream symbolizes perfection, the whole, immortality and / or integrity. On a less positive note, the dream's interpretation is that you ... ml">">
Circus : The dream's interpretation of being at circus is related to your desires for a more interesting life. On the other hand, The meaning of this dream is that ...