To use the rules and procedures meant to protect a system in order to instead manipulate the system for a desired outcome.

(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.

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

(astronomy) A group of stars (and possibly smaller bodies such as planets or asteroids) that orbit one another.

The system of units developed in France in the 1790s and now used worldwide.

A system of measurement in use in the United Kingdom and other Commonwealth countries, now mostly superseded by the metric system; similar to the system currently used in the United States; consisting of units such as the inch, the mile and the pound (of weight).

Any device with inner workings obscured.

(medicine) A blood group system, the second most important after the ABO system, and important in human blood transfusion, whereby blood types are classified according to the presence ("positive") or absence ("negative") of potentially over 50 antigens, of which the most commonly referenced is RhD.

(physiology) The parts of an animal body comprising the heart, blood vessels (arteries, veins, and capillaries), and blood, which circulate the blood around the body.