I understand it perfectly. I understand that it is used to mean whatever someone wants it to mean. When it is used about living things it means undesigned and rice was designed by human hands so it is a false use of the word.
And now I ask for your source.
Not that I've noticed.
I understand that it is used to mean whatever someone wants it to mean.
Then you understand it incorrectly.
When it is used about living things it means undesigned
No, it does not.
and rice was designed by human hands so it is a false use of the word.
Until just the last few years when direct genetic engineering became possible, the refinement of rice was hardly "designed by human hands", it was instead improved by humans who first unwittingly drove the evolution of rice, then later purposely directed the evolution. But it was still done via the process of evolution (reproduction, variation, and selection).
It's not a "false use of the word" at all. Selective breeding (and/or cross-breeding) is still evolution, in every sense of the word.