Two words put together to make one word-:-)
Act with purpose
Act before
Act against
Each sufferer has their own method to counteract their motion sickness.
Well there is counteract and react
See mean-8. Or get a dictionary.
We're not sure what you have in mind when you say "counteract". But two vectors can certainly add up to zero, if their magnitudes are equal and their directions are different by exactly 180 degrees. In that case, they have the same effect as if they were both not there at all.
That is not a word in the English language.
To counteract means to act in opposition to, or to hinder or frustrate.
Offset.
Each sufferer has their own method to counteract their motion sickness.
Well there is counteract and react
The goal of an antacid is to counteract the acids in the body.
The prefix for "counteract" is "counter-".
The word could be toxic, or in its effect deleterious or harmful.
How did Aguinaldo counteract such aggression?
A drug to counteract the poison.
The antidote will partially counteract the effect of the poison. The mayor tried to counteract the bad publicity that the city was receiving.
Unions have attempted to counteract the overall decline in membership by
Words meaning to cancel or make ineffective are void, revoke, annul, counteract, offset, invalidate...