The antonyms for the term "up light" can vary depending on the context of its usage. However, some general antonyms for this word can be "down light," "dim light," "low light," or "reverse light." While up light usually refers to a source of light placed or directed upward, down light refers to a source of light directed downwards. On the other hand, dim light or low light refers to a type of lighting that is not very bright or intense. Finally, reverse light refers to the light that illuminates the area behind a car when it is backing up. These antonyms offer a range of options for contrasting or complementing the concept of up light.