The search textbox has an autosuggest feature. When you enter three or more characters,
a list of up to 10 suggestions will popup under the textbox. Use the arrow keys
to move through the suggestions. To select a suggestion, hit the enter key. Using
the escape key closes the listbox and puts you back at the textbox. The radio buttons
allow you to toggle between having all search items start with or contain the text
you entered in the search box.
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radiation
![listen](https://webarchive.library.unt.edu/web/20120925132536im_/http://www.cancer.gov/images/audio-icon.gif)
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Energy released in the form of particle or electromagnetic waves. Common sources of radiation include radon gas, cosmic rays from outer space, medical x-rays, and energy given off by a radioisotope (unstable form of a chemical element that releases radiation as it breaks down and becomes more stable). |