Definition of contra- in US English:

contra-

prefix

  • 1Against; opposite; contrasting.

    ‘contraflow’
    ‘contradict’
    ‘contralateral’
  • 2Music
    (of instruments or organ stops) pitched an octave below.

    ‘contrabass’
    ‘contralto’

Origin

From Latin contra ‘against’.

Pronunciation

contra-

/ˈkɒntrə/