White whale metaphor

Question

I’m translating an english book in my native language and here is a metaphor I’ve never heard ; the sentence is :

My personal white whale, author Neil gaiman .

What does white whale mean here ?

Answer 1

This is a reference to Moby Dick. It refers to something that someone is obsessed with finding (but will probably never manage to do so) - the potentially mythical object of an endless, life-long quest. See here for more examples.