wiki Root Word: "-onomy"

Latin or Greek Meaning: This Greek word literally means law, order, arrangement, regulation, or systematized knowledge of something.

astronomy: The scientific study of heavenly bodies, particularly stars.

ecoonomy: The management of the resources of a community, country, etc. Since "eco" means "house," the word "economy" literally means "household management."

taxonomy: The classification of organisms (living things like plants and animals) in an ordered system based on presumed natural relationships. The science, laws, or principles of scientific classification.

Astronomy, or the "law of the stars", is one of the oldest branches of science. Astronomy began as man's attempt to explain the motions of celestial objects like the moon, the sun, the planets, and the stars. These objects seemed to follow certain rules or laws; they would disappear and reappear after a certain number of days, weeks, months, years, or some other interval of time.

Johannes Kepler is often considered one of the fathers of astronomy. Kepler was the first scientists to develop a set of equations that could be used to plot and describe the orbits of the planets.

SO WHAT??? SECTION:

Whenever you see "-onomy" at the end of a word, you can be sure that there are going to be a certain set of rules that are going to be involved with what ever you are studying. Astronomers study the "laws" or "rules" that govern the motion of the objects in space. Kepler's laws of planetary motion, Einstein's theory of relativity, Newton's law of intertia (1st Law of Motion) and his law of universal gravity... these are just a few examples of the order and regularity that astronomers see in the universe. Understanding these laws help astronomers to explain why the length of day gets longer in summer, why the moon goes through phases, why some planets seem to wander backwards against the stars, why stars moving away from us will appear more red, etc.

Taxonomists also use specific rules when grouping similar organisms together. For example, sharks and dolphins may look very similar, but a taxonomist would never put them near each other on a taxonomic tree. A cold-blooded shark, with its gills and cartiledge, is going to be grouped with other fish, like a goldfish or trout. In contrast, the warm-blooded dophin, with its 4-chambered heart, its well-developed lungs, its mammary glands, and birth of live young would definately be a mammal (like bears, humans, and whales).

Just remember that "-onomy" means rule or law and you're well on your way to understanding why the economy is driven by the law of supply and demand, and why congress had better balance (manage) the country's budget better or the US economy is going to be in big trouble!

Citations and Sources

Definition of "economy" came from the following wesbite: 

Harper, Douglas. "Economy." Online Etymology Dictionary. Nov 2001. 14 May 2008 <http://www.etymonline.com/index.php?term=economy>.   

Definition and examples of other words using "-onomy" came from the following wesbite: 

"Latin-Greek Cross Reference: nom-, -nomy, -nomical." Robertson's Words for a Modern Age. 2007. Senior Scribe Publications . 9 May 2008

<http://wordinfo.info/words/index/info/view_unit/1406/?letter=a&page=1&spage=1&s=astronomy>

The Kepler cartoon was obtained from the following website:

Harris, Sydney. "On the difficulties faced by astronomy educators." Astronomy-related cartoons by Sidney Harris. 02 Sep 1999. 14 May 2008 <http://astro.wsu.edu/worthey/astro/html/im-sydney-harris/kepler.gif>.

Taxonomy image cam from the following website:

Huffman, Brent. "Explore the Family Tree: Uncovering Ungulate Taxonomy." UltimateUngulate.com - Your Guide to the World's Hoofed Mammals. 02 Jan 2007. UltimateUngulate.com. 14 May 2008 <http://www.ultimateungulate.com/familytree.html>.