whisper noun

ADJ. barely audible, the barest, faint, gentle, hushed, low, mere/the merest, soft | fierce, harsh | audible, loud, stage ‘I knew this would happen,’ he said in a stage whisper (= one that he wanted everyone to hear). | hoarse, husky, strangled | awed, excited, urgent | confidential, conspiratorial

PREP. above a ~ Their voices were very quiet, hardly above a whisper. | in a ~ They spoke in whispers.