This is the 8601st most frequent Spanish word.
saeed
The word "saeed" is not Spanish; it is an Arabic name meaning "happy" or "fortunate" in English.
Here, 'Saeed' is used as a proper noun, the name of a person, to indicate who is performing the action in the sentence.
Saeed está leyendo un libro en la biblioteca.
Saeed is reading a book in the library.
In this case, 'Saeed' is referred to as a noun representing a common name, used here as the topic of discussion.
El nombre Saeed es común en algunos países.
The name Saeed is common in some countries.
'Saeed' is again used as a proper noun referring to a particular individual, helping the speaker specify whom they met.