The term "spread head" can refer to a variety of things. One possible synonym is "wide-brimmed," which refers to a hat or other head covering with a broad brim. Another synonym could be "broad-headed," which might describe a bird or other animal with a wide head or a tool with a broad cutting edge. "Dissemination" is another possible synonym, which refers to the process of spreading information or ideas. Finally, "grandiose" might be a fitting synonym for "spread head" if used to describe someone with an exaggerated sense of self-importance or who tends to overestimate their influence or impact.