This is the 2865th most frequent Polish word.
lepsza
"Lepsza" means "better" (feminine form).
In this sentence, 'lepsza' is the comparative form of 'good,' indicating that someone has a higher quality in a particular skill or attribute.
Ona jest lepsza od innych w matematyce.
She is better than others at mathematics.
Here, 'lepsza' describes a noun ('book') and compares it favorably by suggesting it has superior qualities.
To jest lepsza książka niż tamta.
This is a better book than that one.
In this example, 'lepsza' modifies a noun ('job') as part of an aspirational statement towards an improved condition.