“What had a real boom in development in the early 20th century?” crossword clue

Reveal the answer to see why it works and where this clue has appeared before.TNT is the answer to the New York Times crossword clue “What had a real boom in development in the early 20th century?”. It was last seen in the puzzle of June 27, 2025, where it runs at 34 Across and fills 3 squares. It crosses 3 other entries in that grid — those are listed below and are the quickest way to confirm the letters you already have.