The banana generally symbolizes fertility and fecundity, but can also suggest sensuality. At one time it would have suggested the exotic.
Psychological / Emotional Perspective:
In conjunction with other fruit, it can be taken to mean fertility or sustenance – a bunch of bananas signifies a good harvest. Green bananas means a plan has not yet come to fruition.
Everyday Material Aspects:
Most dreams about fruit are to do with sexuality or the harvesting of past actions. Conventionally, the banana, because of its shape, signifies the penis. However, it is also considered, because of its yielding nature, to represent the correct management of masculine sexuality.
Gender / Specific Meanings:
Other circumstances of the dream will enable you to make a full interpretation. A single banana is more likely to be interpreted by a man in terms of the penis whereas a woman may interpret the same symbol as a caring (nurturing) action.
Consult the entries for Food and Fruit.