Keywords for the Moon: receptive/feminine, reflective, short cycles
Personification: the triple goddess (Isis, Diana, etc.), the mother archetype
Primary symbolism: water, the sea and the cup
Let me make a quick disclaimer about using words like "feminine or mothering" in my discussion. I am using these words in their archetypal sense as representing a principle rather than as a personal attribute. Be we male or female, we all have the archetypal energies of the feminine. That's really what the planets are, symbols of the great archetypes. And a quick check of a natal chart will show that we each own ALL of the energies/planets.
Receptive/feminine
The Moon is our receptive functions and energies more than anything else. Contrast that with the sun, which is the primary outgoing function. This is a simple, but profound concept, this idea of the Moon as representative of our incoming or receptive natures. Nearly all of the classic associations with the Moon can be derived from this one concept.
If we examine how, we take information and experience into our lives, we realize that it just arrives without our awareness. There is far too much incoming data for the conscious mind to process so our receptive selves use the subconscious which does not filter information like consciousness does. For example, we may not be aware of a sound until we turn our attention to it, but our subconscious hears that noise. Thus, the Moon, the receptor, is the subconscious. And since the subconscious is difficult to access for most people, except via dreams, the Moon is associated with unconscious elements of ourselves such as our habits and emotions.
Even as infants we absorb and receive. We are not yet ready to be our outgoing "sunny" selves. So the Moon is also childhood and our experience of our mother, particularly in her role as nurturer. The Moon in a chart shows how the native was nurtured and probably how he, in turn, goes about nurturing others. If we put the concept of early childhood/nurturing with the subconscious qualities of the Moon (and an infant is indeed mostly functioning at a subconscious level), we can begin to understand how the Moon represents our deep-seated issues, both positive and negative. When the Moon in a chart has hard aspects (square, opposition, etc.) or is conjunct an incompatible planet, the issues the native has to deal with will be hard to access because they will be largely subconscious.
When we are on the receiving end of things, we are basically powerless. Stuff just comes at us. It is from this situation that the Moon gets it's association with the public as a large, faceless, powerless mass. However, on a personal basis, the Moon is as powerful in forming the personality as is the Sun. This is because we are all so much formed and influenced by what we receive.
The Moon, however, is not the total feminine archetype in a chart. She owns that portion of the feminine that has to do with nurturing, mothering, receiving. The other portion is owned by Venus and basically has to do with attraction and earthy concerns.
(to be continued)