深奥(しんおう)

深奥(しんおう) refers to the deepest, most hidden aspects of a subject — the profound mysteries that require deep study to reach.

Compounds

深(しん) (deep) + 奥(おう) (inner depths, recesses).

Common collocations

• 深奥(しんおう)を極(きわ)める: to plumb the depths of
• 深奥(しんおう)に触(ふ)れる: to touch upon the mysteries of
• 学問(がくもん)の深奥(しんおう): the profound depths of a discipline
• 自然(しぜん)の深奥(しんおう): the mysteries of nature

Similar words

• 深遠(しんえん): profound, far-reaching (emphasizes depth of thought; used for ideas or philosophy)
• 奥義(おうぎ): secret teaching, esoteric principle (used in martial arts or traditional arts)

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A literary and formal word. Rarely used in casual conversation. Common in academic writing, philosophy, and essays about the arts.