You might be looking for "upsample", which is like resample but specifically for "making more pixels" (in the context of raster images), and is the opposite of downsample.
Interpolation does not necessarily mean upsampling, because downsampling also uses interpolation.
Also be advised that strictly speaking - you're not enhancing, you're not increasing complexity, you're not necessarily increasing resolution. Even more strictly speaking - you're not necessarily increasing the size either.
You're "stretching" (wrong term, but perhaps more natural) an image with a specific amount of pixels across a larger amount of pixels.