In EASA-speak:
- Dry Lease Agreement - An agreement between undertakings pursuant to which the aircraft is operated under the AOC of the lessee.
- Wet Lease Agreement - An agreement between air carriers pursuant to which the aircraft is operated under the AOC of the lessor.
- Damp Lease - A wet lease with partial crew
See Regulation (EU) 1008/2008
In the real world - what Paco said