The original Hebrew term sâtan (Hebrew: שָּׂטָן‎) is a generic noun meaning "accuser" or "adversary", which is used throughout the Hebrew Bible to refer to ordinary human adversaries, as well as a specific supernatural entity. The word is derived from a verb meaning primarily "to obstruct, oppose". When it is used without the definite article (simply satan), the word can refer to any accuser, but when it is used with the definite article (ha-satan), it usually refers specifically to the heavenly accuser: the satan.

Ha-Satan with the definite article occurs 13 times in the Masoretic Text, in two books of the Hebrew Bible: Job ch. 1–2 (10×) and Zechariah 3:1–2 (3×). Satan without the definite article is used in 10 instances, of which two are translated diabolos in the Septuagint and "Satan" in the King James Version. This being the case, is Satan a singular entity or a group of entities? Is "The Satan" used even as "The Angel of the Lord" is?