This is the 307th most frequent Turkish word.
merak
Curiosity.
The word 'merak' is used to express an interest or curiosity towards something here, specifically books.
Onun kitaplara olan merakı çok büyük.
Her curiosity about books is very profound.
'Merak' signifies an intense interest or passion for a topic, in this case, space.
Uzaya olan merakım beni astronomi okumaya yönlendirdi.
My curiosity about space led me to study astronomy.
Here 'merak etme' means 'don't worry', showcasing an idiomatic usage indicating concern.