This is the 598th most frequent Icelandic word.
undirbúning
Preparation.
The term 'undirbúning' is used here as a noun describing the process of getting ready or preparing for the festival.
Við erum í undirbúningi undir hátíðina.
We are in preparation for the festival.
Here, the noun 'undirbúningurinn' refers to the preparations made, with the definite article attached for specificity.
Undirbúningurinn var tímafrekur en nauðsynlegur.
The preparation was time-consuming but necessary.
In this sentence, 'undirbúning' is used in the accusative case as the object of the verb, indicating the action or concept of preparing.