What is the opposite word of basic?

The opposite of "basic" depends on the context in which you are using the word. Here are some possibilities:

If you are referring to something simple or fundamental:

* Advanced

* Complex

* Sophisticated

* Elaborate

* Detailed

* Comprehensive

If you are referring to something ordinary or unoriginal:

* Unique

* Exceptional

* Extraordinary

* Original

* Innovative

* Cutting-edge

If you are referring to something of low quality or low value:

* High-quality

* Luxurious

* Premium

* Exceptional

* Excellent

If you are referring to something lacking in style or individuality:

* Stylish

* Trendy

* Fashionable

* Unique

* Individualistic

Please provide more context so I can give you a more precise opposite.