Formal:
* Distinct: Emphasizes clear separation and individuality.
* Divergent: Suggests moving in separate directions.
* Disparate: Highlights significant differences in nature or quality.
* Unalike: A simple and direct synonym.
* Variant: Indicates an alternative form or version.
Informal:
* Unlike: A common synonym for "different from."
* Unequal: Emphasizes a lack of similarity in size, quantity, or quality.
* Uncommon: Suggests something rare or unusual.
* Distinct from: Similar to "distinct," but emphasizes the separation.
* Not the same: A straightforward, but less formal way of saying "different."
Other options:
* Contrary: Indicates opposition or a contrasting view.
* Opposite: Suggests a complete contrast.
* Alternative: Implies a choice between different options.
The best word to use depends on the context and the nuance you want to convey.