Definition of abelian in English:
 abelian
adjectiveəˈbiːlɪənəˈbēlyən
Mathematics (of a group) having members related by a commutative operation (i.e. a*b = b*a).
 Example sentencesExamples
-  Herbrand also worked on field theory considering abelian extensions of algebraic number fields.
 -  Galois, after reading Abel and Jacobi's work, worked on the theory of elliptic functions and abelian integrals.
 -  In 1925 he proved the Krull-Schmidt theorem for decomposing abelian groups of operators.
 -  In the same year he generalised von Neumann's spectral theorem to locally compact abelian groups.
 -  He does provide an example of the decomposition of an abelian group into cosets of a subgroup.
 -  After submitting a thesis on abelian functions, he received his doctorate in 1895 from the University of Strasbourg.
 -  Schreier showed that the fundamental group of such a space is always abelian.
 
Origin
  
Mid 19th century: from N. H. Abel (see Abel, Niels Henrik) + -ian.