stand up to (someone or something)
To confront someone or something in defiant opposition, especially in defense of oneself or someone else. Wow, I can't believe you stood up to the boss like that. He's such a bully to everyone else. We need to stand up to these big companies that try to pollute our waters.
stand up to someone or something
to take a stand against someone or something; to hold one's ground or principles in the face of a challenge by someone or something. He is a tough customer, and you have to learn to stand up to him. Can the witness stand up to questioning by the prosecution?
stand up to
Confront fearlessly, oppose boldly, as in You've got to stand up to the boss if you want him to respect you. [Early 1600s]
stand up to
To confront fearlessly; face up to.