This is the 2749th most frequent Russian word.
ирины
"Iрины" is the plural form of the name "Ирина" (Irina), which is a Russian feminine given name equivalent to "Irene" in English.
In this case 'Ирины' specifies the author of the poems, emphasizing them as a creation of hers.
Я видел стихи Ирины.
I saw Irina's poems.
The usage here implies the context or scope of discussion is related to Irina and her experiences.
Мы говорили о жизни Ирины.
We talked about Irina's life.
The word 'Ирины' here indicates possession, showing whom the books belong to.