From an unused root meaning to hollow out; the palm; by extension, a handful -- handful, hollow of the hand.
H8168. shoal
[שֹׁ֫עַל] noun [masculine] hollow hand, handful; —
1 hollow hand: suffix בְּשָׁעֳלוֺ Isaiah 40:12 (figurative of ׳י holding waters).
2 handful: plural שְׁעָלִים 1 Kings 20:10 (dust, in hyperb.); construct שְׂעֹרִים שַׁעֲלֵי (as if from [שַׁ֫עַל] Kö ii. l. 35) Ezekiel 13:19 handfuls of barley.