There are several synonyms for the phrase "move downward," each with its own nuances and implications. One possible option is "descend," which suggests a gradual, controlled movement, as in descending a staircase. Another is "drop," which connotes a sudden and possibly violent downward movement, as in dropping a rock into a pond. "Slide" might be used to describe a smooth, effortless downward motion, as in sliding down a hill on a sled. "Fall" suggests a lack of control or agency in the downward movement, as in falling off a ladder. Finally, "sink" might be used to describe a sinking feeling or sense of weightlessness as something moves downward, as in a sinking ship or a person sinking into a chair.