The Sun and all the heavenly bodies that orbit around it, including the eight planets, their moons, the asteroids, and comets.

(astronomy) The combined system or structure formed by all of the rings orbiting a planet

feudalism

(anatomy) The skin, feathers and other outer coverings of an animal.

A burglar alarm.

(taxonomy) A coherent system of taxonomic judgements on circumscription and placement of the considered taxa. A taxonomic system is restricted to a large but limited part of the living world.

(anatomy) A system of organs for the purpose of digesting food.

An informal method of communication used to pass information to US citizens during emergencies.

Any data processing system, either manual or computerized. / Any telecommunications system whose primary function is to transmit and/or display data.

(US, alternative in Canada) A system, policy or understanding based on trust in the honesty, honor, or integrity of others.