This is the 2278th most frequent Turkish word.
bildiren
"Bildiren" means "one who informs" or "informing."
Here, 'bildiren' is used as a participle, modifying 'bilgi' to specify the kind of information.
Gazete yazarları, halkın haberdar olmasını sağlayan bilgi bildiren kişilerdir.
Newspaper writers are people who present information to make the public aware.
In this sentence, 'bildiren' is part of a compound phrase, acting as a participle defining 'memur' (clerk).
Bildiren memurun raporu, toplantıda detaylı olarak tartışıldı.
The report of the informing clerk was discussed in detail at the meeting.
The term 'bildiren' modifies 'yazı' (letter) to describe its purpose or function.