Defluent is a relatively rare word, and therefore may not have many synonyms. However, some possible options include "flowing," "running," "streaming," or "pouring." These words all convey a sense of movement and fluidity, which is similar to the meaning of defluent. Other synonyms may depend on the context in which defluent is being used, such as in describing a river or waterway. Possible synonyms in this case could include "current," "channel," "brook," or "stream." Ultimately, it's important to choose a synonym that accurately captures the meaning of defluent while fitting the tone and language of the sentence or passage.