This is the 4282nd most frequent Dutch word.
binnenin
"Binnenin" means "inside" or "on the inside."
In this sentence, "binnenin" describes the placement of the hidden room, specifying that it is inside the castle.
Er bevindt zich een verborgen kamer binnenin het kasteel.
There is a hidden room inside the castle.
Here, "binnenin" is used to indicate the location of the key, specifying that it is inside the box.
De sleutel ligt binnenin de doos.
The key is inside the box.
The term "binnenin" here denotes an inner emotional experience, referring to feelings within his heart.