Kernel in projective space definition

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This seems to be a very trivial question (just a definition), but I am not able to find an answer on the internet. What is meant by the "kernel in projective space of a linear mapping"? I understand what the kernel is, but I do not understand what it means with the addendum "in projective space." Thanks for all of your help!

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This is just summarizing what was said above: given a linear transformation $T:V\to W$ of (say) finite dimensional vector spaces over a field such as $\mathbb{C}$, we know that $\ker T$ is a subspace of $V$, and as such corresponds to a linear subvariety of $\Bbb{P}(V)$ under the projection $\pi:V\to \Bbb{P}(V)$. That is, $\pi(\ker T)\subseteq \Bbb{P}(V)$ could be interpreted as the kernel in projective space.