Nebule is a term that refers to a cloud, mist, or haze formation that is often seen in the sky. There are several synonyms for this word, including mist, fog, vapor, smog, and haze. Each of these terms describes a different type of nebule formation, and they can be used interchangeably depending on the context. For example, mist is typically associated with a fine spray of water droplets, while fog is a dense cloud that often limits visibility. Vapor, on the other hand, can refer to any gas or liquid that is in a gaseous state, while smog is a mixture of fog and smoke. Haze is a general term that refers to the presence of small particles in the air that can obscure visibility.