The lexical meaning of the noun שָׂטָן śāṭān in biblical Hebrew is "adversary" or the like. It occurs 27x in 23 verses in the Hebrew Bible. In most instances, it is clear this it is best translated by the word "adversary":
- in Psalm 109:6 it clearly refers to a hostile person;
- in the Samuel/Kings references, it refers to human opponents of Israel or its monarchs;
- in the Balaam story (Numbers) it refers to a divine messenger opposing (acting as an obstacle to) Balaam's mission.
That leaves two occurrences in Zechariah, and 14 occurrences in Job. (We'll come to the last one in 1 Chronicles in a moment.) As OP notes, some of these are traditionally translated as "Satan", that is, as if śāṭān were a proper name rather than a common noun. This is a mistake. In each of the occurrences in Job and Zechariah, śāṭān appears with the Hebrew definite article: haśśāṭān = "the satan" -- but names in biblical Hebrew do not take an article, so these occurrences must be a title, not a name. But it is rarely so translated in English Bibles (for e.g. Job 1:6) as "the Adversary" or "the Accuser", although this is demonstrably its meaning.
There is one verse left for comment: 1 Chronicles 21:1. In this late text, "Satan" incites David to take a census, by contrast with the parallel passage in 2 Samuel 24:1, where the LORD has this role. Here, śāṭān appears without the article ("anarthrous" is the fancy term), and uniquely in the Hebrew Bible is plausibly -- indeed, almost certainly -- to be handled as a proper name, not a common noun. It is the first such occurrence, and thus a milestone text for the developing tradition.
Of course the powerful impetus of later tradition, in which "Satan" is regularly a name,1 exerted a strong influence to interpret the "cosmic" characters in Job and Zechariah also in this way. This is clearly an anachronism, though. Apart from the 1 Chronicles text, the rest of the occurrences of śāṭān in the Hebrew Bible are best translated by a gloss like "adversary" or "accuser".
Note
- See on this the work of Jeffrey Burton Russell, and the Satan volume in particular.