Least prime quadratic residue

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I'm not sure I understand what the least prime quadratic residue $l(p)$ of a prime number $p$ is.

For example, $l(2)$ and $l(3)$ do not exist, right? Because the quadratic residue are $0$ and $0,1$ respectively, none of them prime numbers.

But $l(11)=3$, because $5^2\equiv 3 \mod 11$, and $2$ is a non-residue.

Is this correct, or am I misunderstanding que concept?