What does "all right" mean?

Completely correct, as in You have a perfect score—your answers are all right. (It could just as well be put as “all your answers are right.”)
In proper or working order, in a satisfactory way, as in The engine is running all right now. [Late 1800s] Also see turn out all right.
In good health, as in John had the flu, but he's all right now. [Early 1900s]
Not injured, safe, as in It was just a minor accident and everyone is all right. [Early 1900s]
Very well, yes, as in Do you want to leave now?—All right, or All right, we'll stay home. [First half of 1800s] Also see all right with you.
Certainly, without a doubt, as in It's late all right, but it will probably come today. [Mid-1800s]
Hurrah! Good for you, as in All right! your team has done it again! [Slang; mid-1900s]
Also, all-right. Good, satisfactory. For example, This restaurant is all right, or Harry is an all-right guy. [Slang; mid-1900s]

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