Abarim Publications' online Biblical Hebrew Dictionary
Scholars list two roots of the form שעל (s'l), which both may have to do with concavity or lowness:
The root שעל (s'l I) doesn't occur as verb in the Bible. It has two derivatives:
- The masculine noun שעל (sho'al) appears to describe a cupped or hollow hand (Isaiah 40:12) and as such is used as unit of volume (1 Kings 20:10, Ezekiel 13:19).
- The masculine noun משעול (mish'ol), apparently describes a hollow road between vineyards. It's used only once, in Numbers 22:24
The root שעל (s'l II) also doesn't occur as verb in the Bible, and has only once derivative, namely the masculine noun שועל (shu'al), which appears to describe a fox or jackal. This noun also occurs in other Semitic languages; in Assyrian this creature was known as selibu.
Like dogs, foxes or jackals were looked upon with disdain. These creatures proverbially dwelled in ruins (Ezekiel 13:4), ate the flesh of human corpses (Psalm 63:10) and wrecked vineyards, probably because of their habit of digging holes (Song Of Solomon 2:15). Foxes were apparently quite numerous in Palestine, because when Samson wanted to avenge his manly honor after the Philistines had given his wife to his friend, he caught 300 of them and sent them through the lands in pairs tied to burning torches (Judges 15:4).
Whether the two roots שעל (s'l) are formally unrelated or not, these animals were probably colloquially known as Low-Lives or Burrowers.