Wikipedia
In the philosophy of Tibetan Buddhism, specifically in the Madhyamaka view, Svātantrika is a category of Madhyamaka viewpoints attributed primarily to the 6th century Indian scholar Bhāviveka. It is used in contrast with another such subcategory, Prāsaṅgika Madhyamaka.
The key distinction between these viewpoints is whether one works with assertions about the ultimate nature of reality, or if one refrains completely from doing so. If one works with assertions, then that is a Svātantrika approach. Refraining from doing so is a Prāsangika approach.
Besides the technical definitions, the styles of the different approaches are notable. Svatantrika style approaches have a more structured syllogistic form, making assertions with argumentation, whereas the Prasangika approach may make assertions, but with significantly less reasonings for those assertions. Instead they mainly point out errors resulting from taking reasonings to logical extremes.