defendant (n.)

• accessory
• accused
• brawler
• correspondent
• diehard
• disputant
• dissident
• litigant
• litigator
• naysayer
• negativist
• objector
• obstructionist
• opposer
• panel
• party
• plaintiff
• prisoner
• protester
• quarreler
• resister
• respondent
• scrapper
• suitor
• suspect
• witness
• wrangler