What is the biblical definition of clean?

In biblical definition, clean has both physical and spiritual meanings, referring to ritual purity, moral purity, and being acceptable to God. In Old Testament Levitical law, clean versus unclean distinguished animals that could be eaten, such as cows and sheep with split hooves that chew cud were clean, while pigs and shellfish were unclean, and also referred to ritual purity for people, for example a person with skin disease was unclean and had to be isolated outside camp, similar to modern negative pressure isolation for infectious diseases, until priest declared clean after healing. Clean also meant free from defilement by contact with dead bodies or bodily discharges, requiring washing and waiting period. In moral sense, clean meant pure heart and hands, free from sin, as in Psalm create in me a clean heart, meaning undefiled and righteous. In New Testament, Jesus emphasized inner cleanliness over ritual, saying it is not what enters mouth that defiles but what comes from heart, and declared all foods clean, shifting focus from ritual to moral cleanliness. Spiritually, to be clean means forgiven, washed by blood of Christ, and made holy. So biblical clean encompasses ceremonial eligibility to worship, physical hygiene, and moral purity, with ultimate cleanliness achieved through spiritual purification rather than just washing.