This is the 6453rd most frequent Dutch word.
trippel
"Trippel" in Dutch refers to a light, quick, or small step or movement.
The word 'trippel' here is used as a noun describing the softly repetitive sound of steps.
Ik hoorde een zachte trippel op de trap.
I heard a soft trippling sound on the stairs.
The word 'trippel' in this case is inflected as 'trippelt', used as a verb indicating light, quick walking.
De kat trippelt snel naar de keuken.
The cat is trippling quickly to the kitchen.
The usage of 'trippel' here as 'trippelende' functions as a present participle to describe the nature of her silent movements.