Developer meaning : A person or entity engaged in the creation or improvement of certain classes of products. A real estate developer; a person or company who prepares a parcel of land for sale, or creates structures on that land. A film developer; a person who uses chemicals to create photographs from photograph negatives. A liquid used in the chemical processing of traditional photos. (dyeing) A reagent used to produce an ingrain color by its action upon some substance on the fiber. A software developer; a person or company who creates or modifies computer software.