The title Academician denotes a Full Member of an art, literary, or scientific academy

Academy

An academy is an institution of higher learning, research, or honorary membership.The name traces back to Plato's school of philosophy, founded approximately 385 BC at Akademia, a sanctuary of Athena, the goddess of wisdom and skill, north of Athens, Greece. In the western world academia is the...

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In many countries, it is an honorary title

Honorary title (academic)

Honorary titles in academia may be conferred on persons in recognition of contributions by a non-employee or by an employee beyond regular duties...

. There also exists a lower-rank title, variously translated Corresponding Member or Associate Member, (chlen-korrespondent).
"Academician" may also be a functional title and denote a full member of the National Academy

National academy

A national academy is an organizational body, usually operating with state financial support and approval, that co-ordinates scholarly research activities and standards for academic disciplines, most frequently in the sciences but also the humanities. Typically the country's learned societies in...

 of Sciences in those countries where the academy has a strong influence on national scientific life, particularly countries that were part of, or influenced by, the Soviet Union

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

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