From an unused root (akin to zabal) probably meaning to press together; a cake of pressed figs -- cake (lump) of figs.
see HEBREW zabal
H1690. debelah
דְּבֵלָה noun feminine lump of pressed figs, pressed (fig-) cake (Late Hebrew דְּבֵילָה, Aram id., , = Greek παλάθη; Arabic lump, large gobbet or mouthful; compare Assyrian dublu, foundation, & Hebrew synonym אֲשִׁישָׁה DlHA 58) — דְּבֵלָה 1 Samuel 30:12; construct דְּבֶלֶת 2 Kings 20:7 = Isaiah 38:21; plural דְּבֵלִים 1 Samuel 25:18; 1 Chronicles 12:40; — used as food 1 Samuel 25:18; 30:12; 1 Chronicles 12:40; תְּאֵנִים דְּבֶלֶת, as application to boil, or eruption 2 Kings 20:7 = Isaiah 38:21.