(computing) A way programming language classifies values and expressions into types, how it can manipulate those types and how they interact.

(anatomy) The system of organs serving for respiration.

(astronomy) A method of stellar classification in which stars are assigned Greek letters (α, β, γ, etc.) in decreasing order of brightness.

(physics) The portion of the physical universe chosen for analysis, with everything outside the system known as the environment.

(anatomy) The part of blood circulation which carries oxygenated blood away from the heart, to the body, and returns deoxygenated blood back to the heart.

A mathematical model of a system based on the use of a linear operator.

(computing) The software associated with an operating system and supporting utilities, database systems etc.

Alternative spelling of system software

(mathematics) A numerical system of counting in tens.

plural of solar system