Dimday is most commonly used to describe a day that is grey, gloomy and lacking in brightness or light. However, there are a number of synonyms that can be used to describe a dimday, including overcast, cloudy, dreary, murky, dull, somber, bleak, and shadowy. Each of these words conjures up a different image or feeling but all share the same sense of a lack of light and brightness. These words can be used interchangeably with dimday to add variety and depth to descriptive writing or to match the tone of a particular text or conversation.