Answer:
To hinder, impede or frustrate someone from achieving a set goal.
Explanation:
Thwart could either be a noun or a verb, the context determines its part of speech when used in a sentence. As a verb, it depicts that a desire could not be realized because it was frustrated by someone or something.
For example:
i. She did all she could to thwart his plans.
This simply means that she after all successfully impeded him from accomplishing his plans.
ii. Paul's aim to achieve a B in his English test was thwarted by his friend.
This makes us to understand that Paul's friend affected his plans to make a B grade in the test.
