This is the 1396th most frequent Polish word.
strachu
"Strachu" means "fear" in English.
Here, "strachu" is used as a noun, in the genitive case, referring to the fear she experienced earlier.
To doświadczenie wzmocniło jej wiarę w siebie, pomimo wcześniejszego strachu.
This experience strengthened her self-confidence, despite the earlier fear.
"Strachu" is used in the expression "ze strachu" (out of fear). It is also in the genitive case, common after prepositions like "ze" (from/out of).
Zwierzęta ukrywały się w swoich norach ze strachu przed drapieżnikiem.
The animals hid in their burrows out of fear of the predator.
The word "strachu" is in the genitive case, describing the gust/thread of fear the person experienced.