Before dark is a commonly used phrase that refers to a particular time of the day when the sunlight begins to recede, and darkness approaches. It is often used as a deadline for any work that needs to be completed before that time. There are a few synonyms for the word before dark, which are useful for adding variety to your writing or speech. Some of these synonyms include "by dusk," "before nightfall," "at sundown," "pre-twilight," and "prior to the evening hours." These synonyms all convey the same meaning as before dark and can help you to express your thoughts more accurately.