oneiric lucidity

The IKIGAI Journeyを読んでいます。
Scientists have established that most lucid dreams happen in the REM sleep stage, when there is most brain and physical activity, and that there are two main triggers which bring about oneiric lucidity.

1. Something unexpected or strange happens in the dream (for example, places and things that are not exactly as they are when we are awake), which enables us to realize we are asleep. In this way, we continue in the dream, but are aware we are dreaming and are able to interact with the sleeping mind.

2. When we are woken briefly by some external noise, we quickly fall back into the same dream as before, but this time we are aware we are asleep because we were awake seconds earlier.

最初 "lucid dreams" の意味がピンとこなかったのですが、"lucid dreams" を引き起こす原因の説明が続いていたので分かりました。しかし、同じ文の最後に出てきた "oneiric lucidity" の "oneiric" は全く見たことのない単語なので辞書を見ます。

・Oxford English Dictionary: formal Relating to dreams or dreaming.: In this spectacular climax, part oneiric and fantastical, the house on fire becomes, in its pyrotechnical wizardry, a final recalcitrant figure to Australian suburban space.’

・Collins Dictionary: of or having to do with dreams: The special effects are eerily primitive, adding to the ghostly, oneiric atmosphere when he gets there.

'The IKIGAI Journey' には難しい単語、表現はほとんど出てきませんが、唯一この "oneiric" が例外でした。