1. A method or manner of doing something that is not sanctioned, recognized, or authorized by official channels or authorities
They communicated through an unofficial way to avoid bureaucratic delays.
Eles se comunicaram de forma não oficial para evitar atrasos burocráticos.
2. An informal or unofficial channel through which something is accomplished
He got the job through an unofficial way by knowing someone in the company.
Ele conseguiu o emprego de forma não oficial por conhecer alguém na empresa.