Core word: Important-unimportant
Meaningful
having real importance or value
He wanted to feel that his job was meaningful.
The trip turned out to be very meaningful for/to both of them.
a meaningful relationship/discussion
Influential
having the power to cause changes : having influence
She became an (enormously/extremely) influentialcritic/writer.
a highly/very influential book
His theories have become more influential in recent years.
My parents have been the most influential people in my life.
— sometimes + in
She has been influential in establishing programs to help the poor.
Significant
very important
a significant event in the history of our nation
Fish is a significant part of their diet.
It is significant that she never mentioned him.
Prominent
: important and well-known
socially/politically prominent families
The new policy is opposed by prominent [=leading] members of the faculty.
He quickly became prominent in the music industry.