eye opening
Eye opening (adjective) means revealing something surprising that changes how you see a subject. Example: “A week in the warehouse was eye-opening — I had no idea how the orders actually moved.”
How to use eye opening
Learner’s notesIn plain EnglishIt showed you something you didn't know and changed your mind.
Neutral, common in reviews, travel writing and journalism.
'Eye-watering' is different again — it means shockingly large or expensive, as in eye-watering fees.