ECO E47: Nimzo-Indian Defense
ECO E47 is part of volume E — Indian Defenses.
The Lichess chess-openings dataset files one named line under it.
It is Nimzo-Indian Defense: Normal Variation:
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Bd3.
That position has come up in 340,998 Lichess games between players rated 1600 to 2500: White won 48.9%, 6.2% were drawn and Black won 44.8%.