Excellent. I suppose like castle in English, huh?
There are different words for citadel, qal'a or hisar in Arabic, kuhandiz or diz in Persian.
Turkish has a word hisar meaning fortress or castle, obviously taken from Arabic.
The site in Turkey which has been identified as ancient Troy since the time of Schliemann's excavations is known as Hisarlik. I don't know Turkish so I can't say what the -lik suffix means, but it could have gotten the name from looking like a fortress--as it in fact had been in ancient times.