Three merged words: Norse 'skál' (bowl/weighing), Germanic *skalō (shell/fish), Latin 'scāla' (ladder/range).
A graduated range of values; the relative size of something; a weighing device; a fish's flat plate.
Multiple origins merged: the weighing device from Old Norse 'skál' (bowl, scale of a balance); the fish plate from Old French 'escale' (husk, shell), from Germanic *skalō; the graduated range from Latin 'scāla' (ladder, staircase). Key roots: skál (Old Norse: "bowl (weighing sense)"), *skalō (Proto-Germanic: "shell, husk (fish sense)"), scāla (Latin: "ladder (graduated range)").