"Be dimming" refers to the process of becoming less bright or less intense. Synonyms for this word include "fading," "dulling," "waning," "dimming," or "losing its luster." Something that is "dimming" may also be described as "growing dimmer," "losing its shine," "becoming less luminous," or "turning murky." This term is often used to describe the gradual reduction of brightness or intensity in a light source, such as the sun setting or a fire going out. Other related words may include "shrouded," "obscured," "veiled," or "cast in shadow," which suggest a similar reduction in brightness or visibility.