Figure study (5)
I believe the answer is:
maths
This might be a double definition.
'figure' is the first definition.
The answer and definition can be both related to thinking as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'study' is the second definition.
(I know that maths is a type of exact science)
Can you help me to learn more?
(Other definitions for maths that I've seen before include "Subject involving figures (abbr)" , "The science of number, quantity and space" , "A school subject (abbr.)" , "Algebra, geometry, calculus etc (abbr)" , "18 across subject" .)