noun, noun which may take the genitive case particle 'no'
root; origin; source; foundation
Refers to the fundamental basis, root cause, or original source of something. Often used in abstract contexts like problems, ideas, or systems.
問題の大本を探る必要がある。
We need to get to the root of the problem.
この習慣の大本は古い神
The origin of this custom lies in ancient Shinto.
noun
Ōmoto (religion)
Only when written 大本
Refers specifically to Ōmoto, a Japanese new religion founded in the late 19th century. Often seen in the full name 大本教.
See also: 大本教
大本は明治時代に始まった宗教だ。
Ōmoto is a religion that began in the Meiji period.
Search-only mixed kana-kanji form.
根源 is more formal and often used in philosophical or scientific contexts for 'root cause' or 'origin', while 大本 is more everyday and can refer to the fundamental basis of various matters.
原因 is the direct cause of a specific event or result, whereas 大本 points to the deeper, underlying source or foundation.
Compound of 大 (ō, 'big, great') and 本 (moto, 'origin, root'). The reading おおもと is a straightforward combination of the kun'yomi readings of the two kanji.