mythical

先程と同じニュース中から表現を見てみます。

mythicalは「神話（上）の」（『ジーニアス英和辞典　第３版』大修館）を想起しますが転じて「架空の、想像上の」（ibid）という語義もあります。簡単ではございますが確認でした。最後にCambridge Dictionaries Onlineを参照してみますと‘imaginary or not real ’と掲載されていました。(Shou-VR*)

Take care over this Twitter market frenzy
Let’s not be blinded by the glitz and glamour of Twitter and others. Exciting? Undoubtedly. Sustainable? Doubtful.

In other words, these so-called unicorns are as rare as their mythical counterparts. The fear is, of course, that such a pursuit creates a universal sentiment that is self-fulfilling rather than based on fundamentals and economics.

http://www.telegraph.co.uk/finance/comment/10437902/Take-care-over-this-Twitter-market-frenzy.html