extra-, extro-, extr-, exter-

From the outside; from without.

To the outer.

In an outward direction.

To the extreme.

1. Relating to, situated on, existing on, or connected with the outside or an outer part; exterior.
2. Suitable for application to the outside; such as, external paints.
3. Suitable or designed for use only on the outside or surface of something, especially the body.
4. Existing independently of the mind; existing outside the body or mind.
5. Acting or coming from the outside; for example, external pressures.
6. Of or relating chiefly to outward appearance; superficial.
7. Relating to, forming, or from a separate or independent organization.
8. Of or relating to foreign affairs or foreign countries: "They appealed to Britain's minister of external affairs for aid."

1. Ancillary effects of production or consumption for which no internal cost is incurred, typically when the actions of firms and individuals have an effect on others than themselves; such as, pollution of a river that negatively affects the health of people living downstream rather than employees of the firm releasing the harmful material.
2. A similar process having a positive effect; such as, investment by a nation to reduce its carbon dioxide emissions which provides a more stable climate for other nations.

The production of a desired product (usually hydrogen) from a hydrocarbon fuel (methanol, gasoline, natural gas, propane, etc.) by a method in which the fuel is processed before entry into the fuel cell or stack.

1. To draw or pull out, often with great force or effort; such as, to extract a wisdom tooth; or to use tweezers to extract a splinter.
2. To obtain despite resistance; as, to extract a promise.
3. To obtain from a substance by chemical or mechanical action; as, by pressure, distillation, or evaporation.
4. To remove for separate consideration or publication; to excerpt.
5. To derive or to obtain (information, for example) from a source; or to deduce (a principle or doctrine); to construe (a meaning).
6. To derive (pleasure or comfort) from an experience.
7. In mathematics, to determine or to calculate (the root of a number).

1. The act of extracting or the condition of being extracted.
2. Something obtained by extracting; an extract.
3. The result of obtaining something from a source, usually by separating it out from other material: "There were a few snippets of information that I managed to extract from the conversation."
4. The act of copying or removing a passage from a text: "This scene is extracted from the author's memoirs."
5. The removal of a tooth or teeth.
6. In chemistry, the separation of a substance from a mixture by dissolving one or more of the components in a solvent.
7. The ethnic origin or the original nationality of someone's ancestors: "Her husband was of Spanish extraction."

A reduction in the volume of natural gas due to the removal of liquid constituents; such as, ethane, propane, and butane.