Is better an adverb of manner

of superior quality or excellence:

a better coat; a better speech.

morally superior; more virtuous:

They are no better than thieves.

of superior suitability, advisability, desirability, acceptableness, etc.; preferable:

a better time for action.

larger; greater:

the better part of a lifetime.

improved in health; healthier than before.

completely recovered in health.

in a more appropriate or acceptable way or manner:

to behave better.

to a greater degree; more completely or thoroughly:

He knows the way better than we do.

I probably know him better than anyone else.

more:

I walked better than a mile to town.

to increase the good qualities of; make better; improve:

to better one's grades;

to better the lot of the suburban commuter.

to improve upon; surpass; exceed:

We have bettered last year's production record.