A mature person takes responsibility for their actions and words. If you also take responsibility for your actions, then you are a Mature person.
A mature person will value theirs and others' time and will not waste their energy on meaningless stuff.
Though it's human nature to gossip, mature people will most of the time be found discussing ideas rather than gossiping.
A mature person will never neglect you and will listen to you carefully and will understand you.
Mature people always think before they speak or react. It benefits them as their energy is saved by not indulging in unnecessary fights.
Mature people know that everybody has different opinions and perspectives, thus they don’t force their ideas on other people and respect differences.
They value their work and without wasting any time or energy, they focus on how to get good results out of their work.