Maturity genrally means the ability to make a decision and stand by it to the end n0o matter what the outcome.m,mature people make decisions based on the objectives instead of frivilously exploring every option available to us without following any of them to the end outcome
intellectual usually refers to those lessons and life experience we gain through work and school

so intellectual maturity could be said to mean the decisionmaking and stick to it ness that we display in work or school