The Messiah

S 3:45 When the angels said: Maryam, Allah gives you good news of a word from him. His name is The Messiah Isa Son Of Maryam, a dignitary in the dunya and the hereafter and among the Muqarrabun.

A compound name, The Messiah Isa Son Of Maryam? 'Muqarrabun' would signify 'Those brought near'.

S 4:157 And their saying: We killed the Messiah, Isa son of Maryam, the messenger of Allah. And they did not kill him and they did not crucify him but it was made to appear to them. And those who have differed about it are in doubt about it. They have no knowledge of it except the following of assumption. And they did not kill him, of a certainty.

Regarding Isa's death, see my post: Isa's Death

S 4:171 People of the Book, do not exceed in your religion nor say about Allah but the truth. The Messiah Isa the son of Maryam is only Allah’s messenger and his word which he threw to Maryam and spirit from him. So believe in Allah and his messengers and do not say Three. Cease; it is better for you. Allah is only one god. Praise be to him that he should have a child! His is what is in the skies and what is on the Earth. And Allah was sufficient as an agent.

Regarding this verse, see my post: A Brief Note on S 4:171

S 4:172 The Messiah will not disdain to be a slave of Lah’s nor the angels, the Mukarrabun. And those who disdain his worship and are arrogant, he gathers them to him, all.

The angels are Muqarrabun, but Isa would obviously be excluded from being an angel, as he is Allah's word and spirit from it. Should we see the angels as courtiers?

The Muqarrabun

S 5:17 Disbelieved have those who have said: Allah, he is the Messiah the son of Maryam. Say: Then who dominates against Allah in a thing if he wants to destroy the Messiah the son of Maryam and his mother and all those on the Earth? And Lah’s is the dominion of the skies and the Earth and what is between them. He creates what he wills and Allah is almighty.

S 5:72 Those who have said: Allah, he is the Messiah the son of Maryam, have disbelieved. And the Messiah said: Banu Isra’il, worship Allah, my lord and your lord. He who associates with Allah, Allah has forbidden him the Jannah and his shelter is the fire. And the wrongdoers have no helpers.

Allah is the Messiah? Who said that? From an Answering Islam article:

This precision in theological language is not a modern invention or polemic, nor is it simply a matter of splitting hairs, but an essential difference and position held by orthodox Christians even before Muhammad’s time. As Muslim author Neal Robinson noted in reference to an ancient Nestorian reference:

… The text which dates from around 550 CE. concludes a discussion of the Trinity with the words ‘The Messiah is God but God is not the Messiah’. The Qur’an echoes only the latter half of the statement. C. Schedl, Muhammad and Jesus (Vienna: Herder, 1978), p. 531. (Robinson, Christ In Islam and Christianity [State University of New York Press, Albany 1991], p. 197; bold emphasis ours) The Quran and the Holy Trinity: Islam’s Mistaken Views of Basic Christian Doctrines

See also: Who did ever say "God is the Messiah"?

S 5:75 The Messiah the son of Maryam is nothing but a messenger. The messengers passed away before him and his mother is truthful. The two of them used to eat food. See how we make the signs clear to them. Then see how deluded they are!

'The Messengers Passed Away Before Him'

Messengers and Food

S 9:30 And the Jews said: Uzayr is the son of Allah and the Nasara said: The Messiah is the son of Allah. That is their speech with their mouths. They imitate the speech of those who disbelieved before. Allah fight them! How deluded they are!

Regarding 'Uzayr', see: Response to Islamic Awareness: Was 'Uzayr (Ezra) Called The Son Of God?

S 9:31 They have taken their rabbis and their monks as lords instead of Allah and the Messiah the son of Maryam. And they were not commanded but to worship one god. There is no god but him. Praise be to him from what they associate!

Regarding this verse, see: The Quran’s many Gods and Lords: An Analysis of the Worship given to And Deification of Creatures within the Islamic Text

In all of these passages THE Messiah is used. There aren't multiple Messiahs.

Further reading:

Is the Trinity in the Quran?