What's a fancy way to say "interesting"?

A fancy way to say interesting depends on the nuance you want, but there are many elegant synonyms that sound more sophisticated. For something intellectually interesting, you could say intriguing, which suggests it captures your curiosity and makes you want to know more, or fascinating, which means extremely interesting and holding your attention. For something thought-provoking, you could say compelling, which means convincing and holding interest, or captivating, which means charming and holding your attention completely. Other fancy synonyms include engrossing, which means absorbing your attention fully, enthralling, which means holding you spellbound, and absorbing, which means taking up all your attention. For academic or literary contexts, you could use stimulating, which means encouraging thought, or thought-provoking, or erudite if it shows deep knowledge. More formal or literary fancy words include piquant, which means interestingly spicy or provocative, intriguing, beguiling, and alluring. If you want to sound very elegant, you could say it is of considerable interest, it is most engaging, or it is utterly compelling. For example, instead of saying that book is interesting, you could say that book is utterly captivating or that book is intellectually stimulating. Other fancy options include riveting, enthralling, and spellbinding for stories, and curious, noteworthy, and remarkable for facts.