ṣpp / Semitic roots
To press down, cover, overlay.
a. sofa, from Arabic ṣuffa, sofa, from Aramaic ṣippā, absolute form of ṣippətā, a mat, perhaps akin to ṣippā, ṣuppā, carded wool;;
b. Sufi, from Arabic ṣūfī, (man) of wool, from ṣūf, wool, perhaps from Aramaic ṣippā, ṣuppā, carded wool (see above). Both a and b perhaps from Akkadian ṣuppu, solid, massive, compacted (textile), verbal adjective of ṣuppu, to press down, rub down a horse, derived stem of *ṣâpu...