Spiritual Meaning:
It will depend on the state of the cobweb as to the spiritual interpretation. A spider’s web can suggest the symbol of the eight pointed star, the mandala – an aid to meditation – and hence the Buddhist eightfold path to spiritual enlightenment. A dirty cobweb, however, denotes that spirituality is contaminated in some fashion.

Psychological / Emotional Perspective:
The cobweb, because it is easily damaged, signifies indecision, perhaps an idea that has not quite crystallized yet.

Everyday Material Aspects:
On a purely practical level the cobweb symbolizes unused talents and potential which has been allowed to go stale.

You might like to consult the entries for Spider and Star in Shapes / Patterns for further clarification.