神秘|しんぴshinpi[1]atamadaka (head-high)

1. na-adjective, no-adjectivemystery; mysteriousness; secret
   その夢ゆめは私には神秘しんぴだった。↗

   The dream was a mystery to me.

• SynonymミステリーNeutralA loanword for puzzles and inexplicable things; also means mystery novels. 「神秘」 points to wonders beyond human understanding.
• Synonym神秘的しんぴてきNeutralThe adjectival form, used to modify things as in 「神秘的な雰囲気」. 「神秘」 is chiefly a noun, though 「神秘な」 is also possible.
• SynonymミステリアスNeutralLoanword mostly for people with a mysterious air, as in 「ミステリアスな女性」. 「神秘」 is more formal and chiefly a noun.
• Synonym不可思議ふかしぎWrittenWritten word for what human minds cannot grasp, originally a Buddhist term. In daily speech say 「不思議」.
• Synonym不可解ふかかいWrittenWritten word for the incomprehensible and puzzling, often of behavior or events, as in 「不可解な行動」. 「神秘」 suggests unfathomable depth.
• Synonym不思議ふしぎNeutralThe everyday word for anything wondrous or inexplicable, with a broad range. 「神秘」 is weightier, for mysteries beyond human intellect.
• Synonym怪かいWrittenSingle written character for strange things, seen in classical phrasing. Not used alone in everyday speech.
• Related怪奇かいきWrittenWritten word for the eerie and bizarre, common in ghost stories and horror. 「神秘」 suggests a profound, unfathomable wonder.
• Related謎なぞNeutralSomething whose cause or truth is unknown, as in 「謎を解く」. 「謎」 awaits a solution; 「神秘」 lies beyond human reach.
• Related怪しいあやしいNeutralSuspicious or off in some way, usually with a negative shade. 「神秘」 is an awe-inspiring mystery, never suspect.
• Related奇怪きかいWrittenWritten word for the bizarre and unnatural, often tinged with suspicion, as in 「奇怪な事件」. 「神秘」 suggests deep, unfathomable wonder.
• Related深奥しんおうWrittenWritten word for the depths of learning or art. 「神秘」 stresses the inexplicable; 「深奥」 stresses unfathomable depth.
• Related玄妙げんみょうWrittenRare written word for the profound and subtle, said of principles or art. In everyday speech use 「奥深い」 or 「神秘的」.
• Related怪異かいいWrittenWritten word for ghosts, monsters and eerie phenomena. 「神秘」 has no sense of 'ghost' or 'monster' of its own.
• Antonym明白めいはくWrittenAntonym: evidence is conclusive and everything is plain and clear — the opposite of 「神秘」's elusive, unfathomable nature.
• Antonym平明へいめいWrittenAntonym: written word for a plain, easy-to-follow style, mostly of texts — the opposite of 「神秘」's unfathomable depth.

Use 「神秘」 for wonders beyond human intellect, as in 「生命の神秘」 or 「神秘な世界」. For everyday wonders pick 「不思議」, for unexplained things awaiting an answer 「謎」, for the eerie 「怪奇」, and for a mysterious person 「ミステリアス」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 人間にんげんの知恵ちえでは計り知はかりしれないような不思議ふしぎなこと。