The Hebrew noun tumah refers to ritual or moral impurity — the state of being unclean under the covenant law. It is the noun form of the verb tame (H2930) and encompasses a wide range from ceremonial defilement to moral corruption.
Tumah in Levitical law was not primarily a moral category but a ritual one — contact with death, disease, or certain bodily discharges created tumah that required purification before one could approach the holy. But the prophets elevated tumah to its moral dimension: Israel's idolatry and injustice was tumah that defiled the land itself (Ezekiel 36:17). The remedy for tumah is always divine — God promises to remove the impurity of his people (Zechariah 13:2). In Christ, the final tumah — sin and death — is conquered by his resurrection.