Arcana

The noun 'arcana' is a word from Latin. In its own language, its singular and plural forms are regular enough; but in English, they seem irregular. The forms that should be used in academic writing are given here:

The common form	Original language	singular	plural	Remarks
arcana	Latin	arcanum	arcana	'hidden things'; those that were only revealed to initiates. (cf. English adjective arcane

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