There are a number of different opinions concerning the linguistic meaning of the word 'Qur'aan.'
The most popular opinion, and the opinion held by Imaam at-Tabaree رحمه الله, is that the word 'Qur'aan' is derived from qara'a, which means, 'to read, to recite.' 'Qur'aan' would then be the verbal noun (masdar) of qara'a, and thus translates as 'The Recitation' or 'The Reading.' Allaah سبحانه و تعالى says in reference to the Qur'aan,
"And (it is) a Qur'aan which We have divided into parts..." (Sooratul-Israa', 17:106)
and He سبحانه و تعالى says,
"It is for Us to collect it and to Recite it [qur'aanah]. When We have Recited it, then follow its Recitation [qur'aanah]." (75:17-18)
On other other hand, Imaam ash-Shaafi'ee رحمه الله held the view that the word 'Qur'aan' was a proper noun that was not derived from any word, just like 'Torah' or 'Injeel.' 
He recited the word without a hamza. One of the qira'aat  also pronounced it this way.
Another opinion  states that the word 'Qur'aan' is from the root qarana, which means, 'to join, to associate.' For example, the pilgrimage in which 'Umrah and Hajj are combined is called Hajj Qiraan, from the same root word. Therefore the meaning of the word 'Qur'aan' would be, 'That which is joined together,' because its verses and Soorahs are combined to form this book. In this case, the word would be pronounced the same way as Imaam ash-Shaafi'ee رحمه الله pronounced it, without the hamza.
A fourth opinion  is that 'Qur'aan' comes from the word qaraa'in, which means 'to resemble, to be similar to.' Hence, the Qur'aan is composed of verses that aid one another in comprehension, and Soorahs that resemble each other in beauty and prose. 
Yet another opinion is that 'Qur'aan' is from qar', which means 'to combine.' It is called such since it combines stories, commands, promises and punishments. 
However, the opinion that is the strongest, and the one that the majority of the scholars hold, is the first one, namely that the word 'Qur'aan' is the verbal noun of qara'a and therefore means, 'The Recitation.' The proof for this is that it is named such in the Qur'aan (and most of the qira'aat pronounce the word with a hamza), and the word conforms with Arabic grammar as the verbal noun of qara'a.
It may be asked: how does on explain the fact that some qira'aat pronounce the word 'Qur'aan' without a hamza, as it is well known that all the qira'aat are equally authentic? The response to this question is that this particular pronunciation is due to the peculiar rules of recitation (tajweed) of those qira'aat, and affects many words. In other words, the qira'aat that pronounce the word 'Qur'aan' without a hamza do not intend to change the pronunciation of the word 'Qur'aan' itself, but rather this occurs due to a particular rule of recitation (tajweed) that affects many words in the Qur'aan, including the pronunciation of the word 'Qur'aan.' Therefore, even though the pronunciation of the word 'Qur'aan' is different in these qira'aat, the actual word is still the same. 
 The Books given to Prophet Moosaa (Moses) and Prophet 'Eesaa (Jesus) (may peace and blessings be upon them both), respectively.
 The qiraa'a of Imaam Ibn Katheer رحمه الله.
 That of Imaam Abul-Hasan 'Alee al-Ash'aree رحمه الله.
 That of Imaam Yahyaa Ibn Ziyaad ad-Daylamee رحمه الله, better known as al-Farraa', a famous grammarian from Koofah.
 For more discussion of these and other opinions, see Imaam Badrud-Deen az-Zarkashee رحمه الله: al-Burhaan fee 'Uloom al-Qur'aan, Maktabah al-Asriyyah, Beirut, 1972, Vol. 1, pp. 276-278; and Shaykh Muhammad Ibn 'Umar Ibn Saalim Baazmool حفظه الله: al-Qiraa'at wa Atharuhaa fit-Tafseer, Daar al-Hijrah, Riyaadh, 1996, Vol. 1, pp. 23-27.
 This is the opinion of Imaam Ibn al-Atheer رحمه الله in his an-Nihaayah, Vol. 4, p. 30.
 Abu Ammar Yasir Qadhi حفظه الله: An Introduction to the Sciences of the Qur'aan, (Al-Hidaayah Publishing and Distribution, 1999), pp. 24-25.