The term "eyeopener" refers to something that is surprising or enlightening. Antonyms for this word could include "expected," "routine," "mundane," "predictable," "dull," "boring," "unremarkable," "unexciting," "unimpressive," and "average." These words all suggest a lack of surprise or novelty. While an "eyeopener" can be exhilarating or even life-changing, its antonyms are more likely to describe a mundane or uneventful experience. In everyday conversation, these antonyms might be used to describe a familiar routine, a predictable outcome, or a disappointing event that fails to live up to expectations.