The opposite would be important, or necessary, needed, vital, or crucial.
The opposite would be importance, value, or worth.
Unimportant
unimportant
The opposite of compulsory (compelled) would be voluntary or optional.
export export
For critical meaning criticizing (in a negative way), the opposite could be complimentary, praising, or laudatory. For critical meaning vital, the opposite could be secondary, unimportant, or unnecessary.
Antonyms of "native" include minor, unimportant, foreign, alien, outside, secondary, and auxiliary.
If it isn't unnecessary, then it's a necessity. So the opposite is necessary.
For critical meaning criticizing (in a negative way), the opposite could be complimentary, praising, or laudatory. For critical meaning vital, the opposite could be secondary, unimportant, or unnecessary.
Canada is an unimportant country. =)
unimportant
Antonyms for the adjective 'dear' are: despised, inexpensive, unimportant, worthless. Antonyms for the noun 'dear' are: stranger, outsider, interloper, intruder.
The opposite of the gerund overriding would be approving or endorsing.(In the US Congress, the failure to override a veto is confirming it.)The adjective overriding (meaning of primary importance, overarching) has the opposites secondary, insignificant, negligible, or unimportant.