adjective
“indistinct, vague” – Merriam-Webster dictionary
The word was encountered in “What If You Could Choose Between the Fastest Route and the Most Beautiful?” Lex Berko
The sentence that this was encountered in was “But how do you quantify concepts as nebulous as beauty or happiness?”
The author uses this word to say that trying to take the “pleasurable detours” or the best route to pursue happiness and beauty is vague. But then they go on explaining how “we found that if you ask a large enough number of people to pick between two pictures [and choose] which one is more beautiful or which one makes them happier, consensus usually emerges”. The author uses this word to trying to convey the idea that trying to find the best detour to take is vague, because it can be the path not too far off from your destination so you can get there on time, or even the path you prefer more than another because its quiet, has more greenery, or just makes you happy in general.