Not bound by or in accordance with convention : Definition of unconventional adjective from the oxford advanced learner's dictionary. Not following what is done or considered normal or acceptable.
Queen Margrethe II Hosts State Banquet in Honour of the King and Queen
Being out of the ordinary. If you describe a person or their attitude or behaviour as unconventional, you mean that they do not behave in the same way as most other people in. The meaning of unconventional is not conventional :
Unorthodox, original, unusual, irregular, atypical, different, uncustomary the vaccine had been produced by an unconventional technique.
Different from what is usual or from the way most people do things:
