opponent
2 occurrences across the corpus
OT Pseudepigrapha
The Letter of Aristeas 9:51
The king praised him and inquired of another, What is goal of speech? And he replied, 'To convince your opponent by showing him his mistakes in a well-ordered army of arguments.
4 Maccabees 4:25
Have pity then on yourselves, whom even I, your opponent, pity for your youth and your beauty.