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superacid

adjective su·per·acid \ ¦süpə(r)+ \
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Definition of superacid

1 : excessively acid
  • superacid solutions of perchloric acid in acetic acid
2 : having a pH value of 3.5–4.0 —used of a highly acid soil (such as bog peat)

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Origin and Etymology of superacid

super- + acid

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