They generally apply to 2-bedroom units. A dedicated 2-bedroom unit can only be reserved as a 2-bedroom. The 2nd bedroom will usually have 2 queen beds.
A lock-off is made up of a 1-bedroom and a studio with a connecting door. The studio is the second bedroom and will usually have a queen bed and a sleeper sofa. The studio also has a kitchenette.
It can also apply to studios & 1 bedrooms. At BWV, about half of the studios & 1 bedrooms are dedicated, which means they don't connect. The other half do connect, which forms 2 bedrooms or can be used separately. No dedicated 2 bedrooms at BWV.
And, just to be clear, a 2-br dedicated will have 1 exterior door, while a 2-br lock-off will have 2 exterior doors. (sometimes an issue if children will be staying in the 2nd bedroom and you don't want an exterior door from that room).