What does "randomized reductions" in the SVP problem mean?

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The SVP problem in Lattice Cryptography is said to be NP-hard under "randomized reductions". What does the phrase "randomized reductions" mean?

Does it mean the "basis" is randomly transformed? If so, why can we not use LLL(lenstra-lenstra-lovasz) algorithm to get a "more orthogonal" set of basis vectors? And would this reduce the hardness of the SVP problem?

Excuse the use of colloquialism in "more orthogonal". I hope it doesn't make the question ambiguous

EDIT: Source for the definition of the SVP: https://en.wikipedia.org/wiki/Lattice_problem

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The word reduction is used in the context of algorithmic complexity, as @MishaLavrov correctly pointed out.

https://en.wikipedia.org/wiki/Reduction_(complexity)

The definition of SVP never pointed to a randomized transformation of the lattice basis. But, the SVP problem is indeed easier to solve using a "good" basis (short and orthogonal). This can be verified through a quick glance of the GGH cryptosystem.

https://en.wikipedia.org/wiki/GGH_encryption_scheme

And among other basis reduction algorithms the LLL can be used to obtain a "good" basis (short and orthogonal)