Dreaming of saying "hello" to your neighbor typically symbolizes the desire for social connections and the need for harmonious relationships in your waking life. It suggests a friendly and approachable attitude towards others. This dream may also reflect your willingness to extend a helping hand and create a sense of community. Alternatively, greeting your neighbor in a dream may represent your curiosity about their life or a yearning for more involvement in your immediate surroundings. Consider the emotions and interactions experienced in the dream for a more personalized interpretation.