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2. Partly
Kinda sorta, but not really.
If someone says, "My tan is partly real," they mean, it is fake.
1. partly
not fully

The main point:
A half (1/2), a third (1/3), a tenth (1/10), smth without a tenth (9/10), etc. - they are only partly 1 because they are all less than 1, but without them 1 is not form a whole.
What you see in Urbandictionary is only partly true :)
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