5 letters · 7 points in Scrabble
noun an electric railway operating below the surface of the ground (usually in a city)
originFrom French métro, clipping of métropolitain (from Ancient Greek μήτηρ (mḗtēr, “mother”) + πόλις (pólis, “city”)), as in the Chemin de fer métropolitain, an early name for the Paris Métro. This name was a direct translation of "Metropolitan Railway", which was the original name of the earliest part of the London Underground, constructed in 1863.
Etymology from Wiktionary, CC BY-SA 3.0