This is the 766th most frequent Icelandic word.
nýjar
"New" (feminine plural form in Icelandic).
Here, 'nýjar' is used as an adjective describing the plural feminine noun 'bækur' (books), meaning 'new'.
Ég keypti nýjar bækur í gær.
I bought new books yesterday.
In this sentence, 'nýjar' again functions as a descriptive adjective for the plural feminine noun 'hugmyndir' (ideas), indicating something fresh or recent.
Við fengum nýjar hugmyndir frá kennaranum.
We received new ideas from the teacher.
Here, 'nýjar' describes the plural feminine noun 'leiðir' (ways), meaning innovative or newly considered.