Delusive (adjective)

1. Tending to deceive or mislead; deceptive.
2. Giving the false impression of being true or real.

Origin:

From the latin word "deludere" meaning "to mock or deceive".

Examples:

1. He was caught in a delusive dream of fame and glory.
2. His promises of wealth were delusive and she was left penniless.
3. The advertisement was delusive, promising results that it couldn't deliver.
4. The delusive nature of the situation made it difficult to know what was real.
5. The delusive calm before the storm made it hard to prepare for the impending danger.