amicus curiae (n.)

• advocate
• agent
• alternate
• assessor
• attorney
• backup
• barrister
• champion
• chancellor
• counsel
• counselor
• counselor-at-law
• deputy
• dummy
• exponent
• figurehead
• intercessor
• lawyer
• lieutenant
• locum
• master
• mouthpiece
• ombudsman
• ordinary
• pleader
• proctor
• procurator
• proxy
• recorder
• representative
• secondary
• solicitor
• stand-in
• substitute
• surrogate
• understudy
• vicar
• vice
• vicegerent