Transitiveness refers to a property of a verb that signifies an action or event that passes from the subject to an object. Synonyms for transitiveness include actionality, transitivity, causativity, and agentivity. Actionality describes the capability of a word to represent an event or action, while transitivity refers to the relationship between the subject and the object in a sentence. Causativity refers to the ability of a word to indicate that an event is caused by an agent or entity, while agentivity describes the potential for a subject to act on or affect an object. All of these terms relate to the concept of transitiveness, which is a crucial aspect of grammar and sentence structure.