An act or threat causing fear in another individual with a reasonable expectation of harm is known as?

The scenario described, where an act or threat induces fear in another individual with a reasonable expectation of harm, aligns with the legal definition of assault. Assault does not require physical contact; rather, it is characterized by the intentional creation of a fear of imminent harm in another person. The key components involve both the intent of the perpetrator to instill fear and the recipient's reasonable perception of that threat.

In contrast, other options like battery involve actual physical contact or harm, while harassment typically pertains to repeated and unwanted behavior causing distress. Negligence involves a failure to act with the care that a reasonable person would exercise, leading to unintended harm, which does not fit the definition provided in the question. Thus, the accurate identification of the act based on the outlined criteria is indeed assault.