This is the 6539th most frequent Turkish word.
anıttaki
"Anıttaki" means "in/on/at the monument."
Here, 'anıttaki' is used to specify the location of the names, that they are on the monument.
Anıttaki isimler tarih boyunca kahramanların isimleridir.
The names on the monument are the names of heroes throughout history.
In this sentence, 'anıttaki' is indicating where the specific writings are found—on the monument.
Anıttaki yazılar eski Türkçe ile yazılmış.
The writings on the monument are written in old Turkish.
Here, 'anıttaki' is employing locative specification to denote the source of the figures as being on the monument.