Reference for Bava Batra 329:1

אלא אבק לשון הרע

— But the fine shades<span class="x" onmousemove="('comment',' Lit., 'dust', i.e., not actual, but hinted, Or implied slander. (Cf. 'Ar. 15b). ');">¹</span> of slander [were meant].

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