Qur'an
Islamic commentators on the Qur'an have emphasized that pre-Islamic Arabic idolatry made a number of godlings (most memorably the three goddesses al-Manāt, al-Lāt and ʻUzzā) equal associates of Allah (as the Qur'an discusses in the 53rd surat) and the word mushrikūn (singular: mushrik) is often translated into English as "polytheists".
Other forms of shirk include the worship of wealth and other material objects. This is pointed out in the Qur'an in one of the stories of the Children of Israel, when they took a calf made of gold for worship, and for which Moses ordered them to repent. Another form of shirk mentioned in the Qur'an is to take scholars of religion, monks, divines or religious lawyers as Lord/(s) in practice by following their doctrines, and/or by following their rulings on what is lawful when it is at variance to the law or doctrines prescribed by God's revelation. Yet another form, is to treat a prophet, such as Jesus, as God.
Read more about this topic: Shirk (Islam)