The word "scrubbest" can be replaced with several synonyms depending on the context of usage. If referring to the act of scrubbing or cleaning, synonyms could include "scours," "buffs," "polishes," or "abrades." If used in a comparative sense, synonyms could include "cleanest," "neatest," or "shiniest." In a more informal context, "best scrubber" or "top cleaner" could be used instead. It is important to choose the appropriate synonym based on the desired tone and intention of the message being conveyed. Ultimately, the synonym chosen should aid in clear communication and effective understanding between the speaker or writer and the audience.