grammar - What does 「名のある」 mean on this page of Yotsuba&! manga?

I am on ch.82, pg.27 of Yotsuba&! manga. Source : http://raw.senmanga.com/Yotsubato!/82/27

What does bubble in the first panel mean. To be specific,

きっと名のある牛だよ！

主なんじゃね！？

I understand the above lines as,

This is definitely some named/famous cattle (meat)

Isn't this rumoured/famous (cattle meat) ?

I interpreted 「主」as "subject (of a rumour)" from the list of meanings (source : jisho)

1. head (of a household, etc.); leader; master


2. owner; proprietor; proprietress


3. subject (of a rumour, etc.); doer (of a deed)



4. guardian spirit (e.g. long-resident beast, usu. with mystical powers); long-time resident (or employee, etc.)


5. husband

Am I correct here ? Is 「名のある」a relative clause ? And is the usage similar to what's described here ?

Also, I feel like my translation of 「主なんじゃね！？」 feels somehow incorrect, especially 「主」.

Answer

きっと名{な}のある牛{うし}だよ！
主{ぬし}なんじゃね！？

I understand the above lines as,
This is definitely some named/famous cattle (meat)

I think it is a good tranlation.

Isn't this rumoured/famous (cattle meat) ?
Am I correct here ?

No, I don't think so.

主{ぬし}なんじゃね！？ 　　

The phrase could be said:

主{ぬし}なのじゃないか！？

The 「主」 is cattle and also a boss. In this case the phrase could be translated as "Isn't this the boss cattle!?"

Is 「名{な}のある」a relative clause ?

Yes, it is a relative clause and the usage is similar to what's described "here."

If you write 「名{な}のある」 all in kanji, it will be as 「名{な}の有{あ}る」, which has the same meaning 「有名{ゆうめい}な」. 「有名{ゆうめい}な」 is an adjective meaning "famous."

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The difference between 「主｛ぬし｝」 and 「ボス」 in Japanese culture

I'm going to explain how you can properly use 「主｛ぬし｝」 and 「ボス」, which are the title of the creature having supreme power over its group or herd in Japanese language.

On the page of a comics posted by the questioner, there is a word 「牛｛うし｝」 and a 「主｛ぬし｝」. By these words I imagined a phrase : 「牛｛うし｝の群｛む｝れの主｛ぬし｝」 "the leader of a herd of cattle". Inspired by this phrase I posted a photograph showing 「猿｛さる｝の群｛む｝れの主｛ぬし｝」 "the leader of a troop of monkeys".

In Japanese language, you could call the leader of a herd of cattle a 「主｛ぬし｝」, but you couldn't call the leader of a troop of monkeys a 「主｛ぬし｝」, you should call it a 「ボス」 instead. I made a white lie in the monkeys' photograph because of the explanation I'm giving now.

The word 「ボス」 is used as the title of the leader when the leader rules its crowd/herd/troop by giving its power or threat.

In contrast with 「ボス」, 「主｛ぬし｝」 rules over its group with something like dignity derived from such as its exceptional size of the body or longevity unlike threatening power, or in other word his existence itself awes the group and makes him a leader of them.

In addition, 「ボス」 needs a group, but a group does not necessarily need for 「主｛ぬし｝」. 「主｛ぬし｝」 could consist only of himself.

「主｛ぬし｝」 may sometimes could be interpreted even as an owner of the specific nature such as a mountain, a forest, etc. not as a leader of a group.

「主｛ぬし｝」 may be employed to call even distinguished fish in a river, a lake, a pond or a swamp.

For example, there is an expression, "there is a 主｛ぬし｝ of the swamp". In this expression we call a certain fish 「主｛ぬし｝」; the fish is such as a carp or catfish of a big size beyond our imagination dwelling in the swamp for a long long time. Of course, it is common that there are similar fish of the normal size other than this enormously big carp or catfish, but the certain carp or the catfish could be called " the 主｛ぬし｝ of the swamp" even if it dwells there only by itself. In this case, I could imagine that the big fish is called 「主｛ぬし｝」 not as the leader of a group, but as the owner of the swamp by implication.