The name Casluhim in the Bible
The Casluhim are mentioned only once (or twice) in the Bible. In Genesis 10:14 they are listed under the descendants of Mizraim, son of Ham, son of Noah. The second time the Casluhim are mentioned in the Bible is in the mirror text of 1 Chronicles 1:2.
Etymology and meaning of the name Casluhim
The etymology of this name is uncertain. Jones' Dictionary of Old Testament Proper Names cites Jerome and reads Their Boundary Protected. Fuerst's Hebrew & Chaldee lexicon to the Old Testament assumes relations with cognate words ks meaning mountain, and lh meaning to lighten burn, shine, make dry. The whole name would mean Dry, Barren Mountain. Both the NOBSE Study Bible Name List and BDB Theological Dictionary remain quiet about a possible meaning.
To a Hebrew audience, however, the dominant segment כסל, which comprises the initial part of the name, looks a lot like the verb (kasal), meaning to be foolish:
Since all other meanings are deeply hidden, to a Hebrew audience the name Casluhim must have sounded similar to either Orionites or Bunch Of Morons.
And if that isn't bad enough, the segment סלח (salah) means forgive, pardon. Together with the particle כ (ke), as if, like, the name would also means As If They Forgive, or As If They Were Forgiven, which seems to express a doubt and doesn't sound very positive; the Casluhim are the Fools.
Another name that may have to do with the constellation Orion is that of the mysterious race of the Nephilim.