だいぶぶん大部分daibubun
1.

A term that refers to the greater share or majority of something, indicating that it encompasses almost all of it while leaving only a small fraction aside.

2.

A word used to describe the significant portion of a whole, often implying that a consensus or commonality exists among the majority of elements within that whole.

3.

An expression denoting a predominant segment of a particular entity, suggesting that this portion plays a crucial role in defining the characteristics or opinions of the entire group.

Example:

石炭は大部分が炭素から成っている。