The term "sluice out" has various synonyms depending on the context in which it is used. If the term is used in a technical context, the synonyms that can be used include "flush out", "rinse out", and "cleanse out". In a general context, "purge out" or "evacuate" or "empty out" can be used as a synonym for "sluice out". If the term is used in the context of a water system, "drain out", "discharge out" or "flow out" can be used as synonyms for "sluice out". Regardless of the context, each synonym for "sluice out" implies the removal of something by washing, purging, or draining it out of a system.