Linear operatorsSee also what's at Wikipedia, your library, or elsewhere.
Broader term:Narrower term:Used for: Linear maps
 Maps, Linear
 Operators, Linear
 Linear map

Filed under: Linear operators
Filed under: Jacobi operators
Items below (if any) are from related and broader terms.
Filed under: Operator theory Holomorphic Spaces (1998), ed. by Sheldon Jay Axler, John E. McCarthy, and Donald Sarason (PDF files with commentary at msri.org)
Filed under: Differential operators
Filed under: AtiyahSinger index theorem
Filed under: Elliptic operatorsFiled under: Spectral geometryFiled under: Operator algebras Operator Algebras and Quantum Statistical Mechanics, by Ola Bratteli and Derek W. Robinson
Filed under: Noncommutative differential geometry 