A self-contained page or group of pages meant to supplement a larger website(noun)
A small area with distinctive ecological characteristics(noun)
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Use "microsite" in a sentence
"/LG's Ally-Iron Man 2 microsite is now live | Android Central »"
"The Hindustan Times/Google election microsite is based on Google gadgets which allows you to add individual features to your iGoogle page."
"Venues will also be rendered in 3D on Google Earth, and on the official Winter Games website. microsite, which is available in 40 languages, will harness Google's relationship with Twitter to bring real-time search results for the Games, including tweets, blogs and articles, directly on to the page."