arcane

 Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++ar·cane /ɑːˈkeɪn $ ɑːr-/ adjective  SECRETsecret and known or understood by only a few people 秘密的；晦涩难懂的 the arcane language of the law 晦涩难懂的法律语言

Examples from the Corpus

arcane• Anecdotes of legal excess reflect the world we see around us and add a human dimension to an otherwise arcane issue.• It is not exactly arcane knowledge.• the arcane language of lawyers• The arcane language of the Treaty of Tlatelolco needs a little clarification.• They evoke romantic images of humming orchard hives and summer sweetness, presided over by veiled eccentrics steeped in arcane lore.• Merely reading what some one has written is less commendable than saying the same thing for arcane reasons.• They wore helmets suggestive of the heads of flies, and their black silks were embroidered with arcane silver hieroglyphics.• They noted that he was a master of arcane tax jargon, not an area that gets the blood racing.• Written on the boxes is all manner of strange titles, fantastic claims and arcane technical terms.Origin arcane (1500-1600) Latin arcanus “secret”, from arca; → ARK

ar·cane adjectiveChineseSyllable  

and only Corpus or known secret understood few a by

arcane
ar‧cane /ɑːˈkeɪn $ ɑːr-/ adjectivesecret and known or understood by only a few people:
    the arcane language of the law

ar·caneBrE /ɑːˈkeɪn/ 🔊NAmE /ɑːrˈkeɪn/ 🔊 adjective (formal) secret and mysterious and therefore difficult to understand 神秘的；晦涩难懂的