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contraoctave

American  
[kon-truh-ok-tiv, -teyv] / ˌkɒn trəˈɒk tɪv, -teɪv /

noun

Music.
  1. the octave between the second and third C's below middle C.


Etymology

Origin of contraoctave

First recorded in 1890–95; contra- 2 ( def. ) + octave