This is the 745th most frequent Estonian word.
pisut
A little; slightly; somewhat.
Here, 'pisut' is equivalent to 'a bit' or 'a small amount', indicating a small quantity of cake consumed.
Ma sõin pisut kooki.
I ate a bit of cake.
In this sentence, 'pisut' modifies 'rohkem' (more), signaling a small additional quantity of time.
Meil on aega pisut rohkem kui tund.
We have a bit more than an hour of time.
Here, 'pisut' is used to describe a slight degree of nervousness, showing its adverbial usage to soften the intensity of the adjective 'närvis' (nervous).