Translation guide
The English phrase "greater part" refers to the majority or most of something. In Japanese, this concept is expressed through various words and patterns depending on what is being quantified (e.g., time, objects, people) and the level of formality.
Expressing that something constitutes the larger portion of a whole, such as time, objects, or abstract concepts.
A common and versatile noun meaning 'most' or 'greater part'. Can be used for both concrete and abstract things. Often followed by は or が.
Referring to the physically larger portion of something, such as a space, body part, or object.
大部分 is a noun and often used with の to modify another noun (大部分の〜). ほとんど is an adverb and can directly modify verbs or be used with の. ほとんど implies a higher percentage (close to 100%) than 大部分, which simply means more than half. In casual speech, ほとんど is more common.
The greater part of the work is finished.
大部分の人が賛成した。
The greater part of the people agreed.
Similar to 大部分, but often implies a slightly larger majority (more than half). Common in both spoken and written Japanese.
時間の大半を勉強に費やした。
I spent the greater part of my time studying.
An adverb meaning 'almost all' or 'most'. Very common in everyday speech. Can be used with nouns (ほとんど + の + noun) or verbs.
ほとんどの学生がその映画を見た。
The greater part of the students saw that movie.
宿題はほとんど終わった。
The greater part of the homework is done.
A pattern meaning 'many of' or 'most of'. Used with nouns. Slightly more formal than ほとんど.
参加者の多くは女性だった。
The greater part of the participants were women.
Also used for physical parts. Context makes the meaning clear.
この土地の大部分は森林です。
The greater part of this land is forest.
Can be used for physical areas as well.
部屋の大半を本棚が占めている。
The greater part of the room is taken up by bookshelves.