If "fancy" means elaborate or ostentatious:
* Plain
* Simple
* Basic
* Unpretentious
* Down-to-earth
If "fancy" means stylish or fashionable:
* Unfashionable
* Out-of-date
* Old-fashioned
* Drab
* Unstylish
If "fancy" means liking or wanting something:
* Disliking
* Averse
* Indifferent
* Uninterested
If "fancy" means imagining or thinking about something:
* Real
* Actual
* Concrete
* Tangible
It's important to consider the specific meaning of "fancy" in the sentence to choose the most appropriate antonym.