Where is Gillian from?

Meaning of the name Gillian

Medieval English feminine form of Julian. This spelling has been in use since the 13th century, though it was not declared a distinct name from Julian until the 17th century [1].

Characteristics of the name Gillian

How do we know this about Gillian

(and is it secret spies?)

We use a combination of data from the internet, and our own Machine Learning models to make these predictions.
In a gist, we use a Machine Learning model trained on a diverse global dataset of 100m+ names, and use it to predict different traits for a person based on first name!
NameGuessr guesses a person's nationality, age, and gender based on their name. We also try to give insightful info around the name's origin, name meaning, and name pronounciation.