megalopolis n.

"great, large; much, abundant; a great deal," a dialectal survival of Old English micel, mycel "great, intense, big, long, much, many," from Proto-Germanic *mekilaz (source also of Old Saxon mikil, Old Norse mikill, Old High German mihhil, Gothic mikils), from PIE root *meg- "great." Its main modern form is much (q.v.); the common Middle English form was muchel. The phonetic development of the dialectal survival is obscure and might reflect Old Norse influence. Related: Mickleness. Middle English had muchel-what (pron.) "many various things."

"ancient Greek city-state," 1894, from Greek polis, ptolis "citadel, fort, city, one's city; the state, community, citizens," from PIE *tpolh- "citadel; enclosed space, often on high ground; hilltop" (source also of Sanskrit pur, puram, genitive purah "city, citadel," Lithuanian pilis "fortress").