A rare or obsolete scientific instrument designed to measure or observe something about sound or resonance (from Greek roots meaning 'self-sound-viewer').
From Greek autos 'self' + echo 'sound' + skopein 'to view/examine.' This is a technical neologism that never gained wide use in scientific practice.
Autechoscope is a perfect example of how scientists used to coin new compound words freely from Greek—modern scientists would probably just call it a 'resonance detector' instead.
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