Is that sentence grammatically correct?
The words are grammatically correct as part of a sentence.
Context is always important; labelling is rarely important.
Your idea is just about right. Please see my amendments above. Remember to use the correct constructions when asking about definitions:
Is this correct?
Does it mean this?
Does this mean ...?
What does this mean?
Is it mean this? X
Is mean ...? X
What this word mean? X
What this word means? X
The subject and verb are understood.
It (Rome) was not nearly as beautiful as you.
Context is always important; labelling is rarely important.
Dialogue in films is not always in full sentences and subtitles don't always exactly translate the dialogue. It's important to remember that.
However, in the dialogue above, your earlier definition is just about right. Person A is saying that Rome is beautiful but that person B is much more beautiful than Rome.
Thank you both for your replies.
***** NOT A TEACHER *****
The teachers have already given you the answer.
I just thought that you would be interested in this:
A few (very few!) people prefer to use "so" in negative sentences:
Rome is not nearly so beautiful as you.
***
Those "few" people explain it this way:
English speakers hear "as ... as" so often that it is better to use "so ...as" for
negative sentences because it will make a bigger impression. Those "few"
people feel that "You are not so nice as my last teacher" will make a stronger
impression than "You are not as nice as my last teacher."