Question: The root word in `미남이시라구요` is `미남` (Noun) to mean `a handsome man` and the full translation for the sentence "changes the noun to adjective" to mean `you're handsome` or is it just a short form of the sentence, `you are a handsome man`?:

> 
> 미남 -> beau / handsome guy
> 
> 
> 미남이시라구요 -> you're handsome
> 
> 
> 

How should the sentence be split:

> 
> 미남이시라구요 -> 미남 | 이 | 시 | 라구요
> 
> 
> 미남이시라구요 -> 미남 | 이시라구요
> 
> 
> 

If it's the first case, what does `이`, `시` and `라구요` mean individually?

If it's the second, then what does `이시라구요` mean?

Or is it not any of the two and the sentence should be split and understood different?

Answer: 
미남이시라구요 is splited into
미남 + 이다 + (으)시 + (이)라구요

이시라구요 is derived from the verb 이다(is).
시 is the honorific form, giving respect to that 미남.

라구 comes from the quotation grammar (Someone said ...) for 이다, namely (이)라고. You see 구 instead of 고 since 구 is the colloquial version of 고.

So a more accurate translation will be:

It is said that he is a handsome man.
미남이시라구요 consists of one noun, two particles, and two verb endings. Let's decompose it like this:

* Take the noun 미남 and attach a particle (a copula) 이다, to make 미남이다, which makes it an adjective("descriptive verb").
* Take the adjective 미남이다 and stick a subject honorific verb ending -시-, which becomes 미남이시다.
* Take the adjective 미남이시다 and stick a vulgar quotation verb ending -라구, which becomes 미남이시라구.
* Take the adjective 미남이시라구 and stick a listener honorific particle 요, to make it 미남이시라구요.

So the 이 means it's a predicate, and 시 indicates the omitted subject of this sentence is a person of a higher hierarchy than the speaker, 라구 indicates a quotation, and 요 indicates the listener of this sentence is a person of a higher hierarchy than the speaker.

A translation would be:

> 
> I heard he is a handsome man.
> 
> 
>