(noun) the chief lawyer of a legal department of a company, government authority or other organization. “The General Counsel represents the Commission in litigation in federal courts, recommends decisions in adjudicatory matters before the Commission, and performs a variety of legal functions regarding internal and other administrative matters.”

in-house counsel: lawyer working at a company; corporate counsel. The top in-house counsel may be referred to as the general counsel. "She left private practice to work as in-house counsel at a large oil company."
defense counsel: (UK spelling: defence): lawyer representing a defendant in criminal or civil actions. "Her defense counsel had considerable experience in defending money laundering cases."
opposing counsel: lawyer representing the other side (the opponents) in a dispute. "She was a good lawyer and generally found it easy to cooperate with opposing counsel."

Source: TransLegal