The word "jaculus" is a Latin term that means dart or javelin. In English, there are several synonyms for this word, including lance, spear, arrow, projectile, dart, and missile. All of these words have a similar meaning to jaculus and refer to an object that is thrown or shot towards a target. These words are frequently used in literature and poetry to describe the action of throwing or launching a javelin, spear, or other weapon. Additionally, these synonyms can be used in a broader sense to describe any object or idea that is focused and precise in its delivery, similar to a dart hitting its intended target.