I've always loved the word archipelago - it just has a pleasing ring to it, I guess - but I like it even more now that I know the etymology. Originally, the word specifically referred to the islands in the Aegean Sea, but over time it came to mean any cluster of islands in general. This was borrowed at the beginning of the sixteenth century from Italian arcipelago, which then referred to the entire Aegean. In Ancient Greek, this was the proper noun arkhipelagos, which may be translated as "the Chief Sea", a term that reflects the water body's importance to the Greeks. Arkhi- more literally means "leading" and, through the verb arkhein (meaning "to rule"), derives from the Proto-Indo-European reconstruction hergh, with the same definition. Pelagos stood in for "sea" and possibly comes from Proto-Indo-European pele, meaning "flat", but that's not certain.
Adam Aleksic, a rising sophomore studying linguistics and government at Harvard University, has been described as the internet's sixth most famous etymologist. He also has disturbing interests in politics, vexillology, geography, board games, conlanging, and law.