De or het gezwindheid?

The correct Dutch article is:

de gezwindheid

Rule Words ending in -heid: almost always de. See the rule
Meaning (Dutch) rapheid, snelheid, vaart, vlugheid

How to use gezwindheid

the gezwindheidde gezwindheid
this gezwindheiddeze gezwindheid
that gezwindheiddie gezwindheid
our gezwindheidonze gezwindheid
your gezwindheidjouw gezwindheid
every gezwindheidelke gezwindheid
which gezwindheid?welke gezwindheid?
a big gezwindheid / the big gezwindheideen grote gezwindheid, de grote gezwindheid

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