"Sanketa vacanam saccam - loka sammuti karanam
Paramattha vacanam saccam - dhammanam tathalakkhanam"
According to the above quote, all the words (cenventional truth) made by living beings using any language considered as truth because they are enacted by living beings.
We use words to mention ultimate truth. For example when we say "Nibbana", the real dhamma or actual Nibbana exists but the word "Nibbana" has been enacted. The actual dhamma and the word used to refer it are two different things. The word may not contain the actual characteristics inherent to Nibbana. I suppose Shakyamuni Tatagata Lord Buddha used many words to explain ultimate truth (Citta, Cetasika, Rupa, Nibbana) because of this reason.
So my question is: Does the word "Nibbana" (as well as the other words used to mention ultimate truth) belong to the conventional truth while only the actual dhamma belong to the ultimate truth?