Pronunciation: [bˈɪɡ t͡ʃˈiːz] (IPA) 
The phrase "big cheese" refers to someone who is powerful or important, and is often used colloquially. The spelling of this phrase is relatively straightforward, with "big" pronounced as /bɪɡ/ and "cheese" pronounced as /tʃiːz/. The "ch" in "cheese" is pronounced with a "ch" sound as in "chair". The word "cheese" itself comes from Old English cēse, and has been used to describe a variety of dairy products since the Middle Ages.
The term "big cheese" refers to an influential or important person who holds a position of authority or power within a particular organization or group. This slang expression is typically used informally to describe someone who is considered significant, influential, or highly regarded in their field or industry. The phrase originated in the United States during the early 20th century and has since become widely used in informal English.
The term "big cheese" often implies that the person in question has achieved a high level of success, expertise, or seniority within their respective domain. This individual is often seen as a leader or decision-maker who holds significant sway in determining the course of action or direction within an organization or community.
The figurative usage of "big cheese" likens the person being described to a large wheel of cheese that is visible, prominent, and commands attention. Just as a large wheel of cheese stands out and is noticed among smaller pieces, the "big cheese" stands out among their peers due to their influence or notable accomplishments.
While the term can be used humorously or playfully in some contexts, it generally connotes a sense of respect or admiration for the person's achievements or status. However, it is important to note that the term can also be used sarcastically or ironically in certain situations, where it may imply a level of disdain or mockery towards a person's perceived self-importance or undeserved authority.
The exact etymology of the term "big cheese" is uncertain, but it is believed to have originated in the United States in the early 20th century. It is a slang expression that means an important or influential person, often used to refer to someone in a position of power or authority.
One theory suggests that the term may have originated from the Urdu word "chiz" or "cheez", which means a thing or an object. As the British ruled India during the colonial times, some words of Indian origin entered the English language, and it is possible that "chiz" or "cheez" made its way to the United States.
Another theory speculates that "big cheese" could have emerged from the metaphorical comparison of a high-ranking person to a dairy product. Cheese, being a larger and more valuable component, became associated with an important or influential individual.
