Sentence:  The nation's southernmost transcontinental Interstate, I-10, serves as the Gulf Coast's "Main Street." Every major city in the <WSD>megapolitan</WSD> area lies along its path. ... <WSD>Megapolitan</WSD> Areas are integrated networks of metropolitan and micropolitan areas. 
Meaning of the word marked with <WSD> tags:  Of or pertaining to a (complex).