Abarim Publications' online Biblical Hebrew Dictionary
The root group עצם ('asam) has three members according to BDB Theological Dictionary but only two according to the more recent HAW Theological Wordbook of the Old Testament. But then, HAW complains that BDB "confusingly lists four," so even the experts seem to have trouble on multiple levels. But we'll stick to the BDB index:
The root-verb עצם ('asam I) is a verb very rich in meaning. It basically denotes strength in numbers: to be mighty (Genesis 26:16, Daniel 8:8), or to be numerous (Exodus 1:7, Isaiah 31:1).
This verb yields the following derivatives:
- The masculine noun עצם ('osem) meaning might (Deuteronomy 8:17). In Psalm 139:14 this word is used to mean bones or frame.
- The feminine version of the above עצמה ('osma) means strength and is only used in Isaiah 40:29.
- The feminine noun עצם ('esem) a very common noun meaning bone (Exodus 12:46, Micah 3:2), or one's whole body (Psalm 6:2, Exodus 24:10). In Jeremiah 50:17 this word is used as a verb, meaning to gnaw on bones.
- The adjective עצום ('asum) means mighty or numerous (Genesis 18:18).
- The feminine noun תעצמה (ta'asuma) is a plural and intensive form meaning might but a whole lot of it (Psalm 68:35 only).
The verb עצם ('asam II) means to shut or close. It's used only twice, both times by the prophet Isaiah and both times to speak of eyes closing (Isaiah 29:10 and 33:15).
Assumed root עצם ('asam III) means to defend, says BDB, but it isn't used in the Bible so we don't really know. Derivative עצמות ('asumot) as used only in Isaiah 41:21, means defense, says BDB. But no, says HAW, it means strong reasons and comes from asam I.