How does the not symbol affect this formula?

Question

I'm trying to understand what

$\lnot x < y$

would mean. Is it that x is not less than y?

Answer 1

Since $x<y$ means that $x$ is less than $y$ and $\neg$, as you know, is the symbol for "negation", the formula $\neg(x<y)$ means that it's not the case that $x$ is less than $y$. Equivalently, this means that $x$ is at least as big as $y$: $$x\geq y$$