This is the 848th most frequent Estonian word.
üpris
"Üpris" means "quite" or "rather" in English.
Here, 'üpris' is used to mean 'rather, fairly' to mildly emphasize the adjective 'interesting'.
See on üpris huvitav raamat.
This is a rather interesting book.
In this sentence, 'üpris' denotes 'quite, fairly' to indicate a moderate intensity of the adjective 'warm'.
Ilm on üpris soe täna.
The weather is quite warm today.
'Üpris' in this context modifies the adverb 'quickly,' indicating a moderate degree of speed.