What does it mean when someone is "brilliant"?

It means ‘very clever’ - but is often used as simply meaning ‘very good’. A light can also be brilliant, meaning it is very bright (and if a person is bright it means they’re clever, too).

Usually "intelligent" but can also be "bright."

I noticed that especially some British/Irish people use it in a way of saying "great" "wonderful" etc. Like \- Oh, we already have the thing, brilliant! edit: Sorry I missed the part where you asked usage specifically for "someone", yeah in that case it is like being smart, clever etc.

I normally hear it used to mean “extremely smart.”

When talking about a person, it means they are extremely smart / clever in a noticeable, stunning way. It implies that the intelligence is obvious, visible and remarkable in the way the person talks, behaves and interacts with others or their environment. Someone can be extremely smart or clever, but you won't notice it either because they're shy, awkward, discreet, maladaptive or even asocial. In that case, brilliant won't be used to describe them, even though they have extreme intelligence within them.

In this case, the writer likely means the definition related to light - she shines so brightly, she is brilliant, like a diamond. It’s more common for it to mean intelligence, but that doesn’t fit well in the sentence above

Bot?

Did you look up "brilliant" in a dictionary?

Brilliant means “very smart” in American English. But British people use brilliant to mean “very good”, or sarcastically to mean “very bad”

Literally, it means bright, like a strong light. It is therefore often used to mean bright in the intellectual sense - "Taylor is brilliant" = "Taylor is very smart/intelligent". Colloquially, it has also evolved to be synonymous with wonderful, terrific, or fantastic, meaning simply "very good", and I think that's how it's being used here. They're just saying they think Taylor is really great in a multitude of ways.

Brilliant - extremely smart; intelligent beyond words; genius. Can also be used as an exclamation or interjection for something that is a good idea. Can also be used sardonically. Examples: “Albert Einstein was a brilliant man.” “Despite his notoriety, Elon Musk is a brilliant scientist.” Versus “That idea is brilliant!” or “Brilliant!” (or sarcastically) “Oh yeah, that’s idea is BRILLIANT 🙄” Much of the later depends on vocal tone and body language for full understanding, but when someone says brilliant positively they generally will act excited. I hope this helped!!!

A brilliant gem attracts your attention in the same way a brilliant person does.