What term is used to describe the act of one human being killing another?

The term used to describe the act of one human being killing another is "homicide." Homicide encompasses all instances where one person causes the death of another, whether it is intentional or due to reckless behavior, and can include a variety of circumstances and legal distinctions.

Manslaughter refers to a specific type of homicide that generally implies a lack of premeditation and is often characterized by circumstances that might mitigate culpability, such as provocation or lack of intent to kill. Murder, on the other hand, usually involves intent and is classified as a more serious offense as it often includes premeditated actions or malice aforethought.

Assault is fundamentally different as it pertains to the act of causing apprehension of harmful or offensive contact, rather than resulting in death. Therefore, while all these terms relate to acts of violence, "homicide" is the broad and inclusive term that accurately captures the act of one person killing another.