De or het priesterkleding?

The correct Dutch article is:

de priesterkleding

Rule Words ending in -ing: almost always de. See the rule
Meaning (Dutch) de ambtskleding van een priester

How to use priesterkleding

the priesterkledingde priesterkleding
this priesterkledingdeze priesterkleding
that priesterkledingdie priesterkleding
our priesterkledingonze priesterkleding
your priesterkledingjouw priesterkleding
every priesterkledingelke priesterkleding
which priesterkleding?welke priesterkleding?
a big priesterkleding / the big priesterkledingeen grote priesterkleding, de grote priesterkleding

Meaning, plural, diminutive, pronunciation and translations: WikiWoordenboek (Dutch Wiktionary) (CC BY-SA 4.0). Example sentences: Tatoeba (CC BY 2.0 FR).