Upper
comparative: more northern (or further north) superlative: northernmost
We usually use more northern for the comparative and northernmost for the superlative. Ordinarily, you'd expect northerner for the comparative of northern, but there is a very common noun northerner, which may be why the Frenchified "more northern" is the usual form. Again, you'd expect northerrnest as the comparative, but with directions, such as northern and southern, top and bottom, upper and outer and so forth, the superlative is usually formed by adding -most: northernmost, uppermost etc.
"Litter" is a noun and a verb and, as such, does not have a comparative degree.
smoother is comparative of word smooth.
A comparative for the word ineffectual is more ineffectual.
comparative
comparative
comparative
Dative ; sharp Comparative ; sharper Superlative ; sharpest.
What's the comparative and superlative of the word "exact"
The synonym for the word "comparative" is "relative" or "analogous."
Worse is the comparative word.