Learner's definition of UNOFFICIAL
not official: such as
not formally chosen by an official decision or vote
not done or made in a formal way by someone in a position of authority
Unofficial estimates of the number of people killed in the earthquake range from 3,000 to 5,000.
I am including an unofficial translation of the speech.
not having the authority to make a statement, decision, etc.
not done in a public and formal way as part of someone's job