Scots rant about differences (9)
I believe the answer is:
contrasts
'differences' is the definition.
The answer and definition can be both related to thinking as well as being plural nouns.
Perhaps there's an association between them I don't understand?
'scots rant about' is the wordplay.
'about' indicates an anagram.
'scots'+'rant'='scotsrant'
'scotsrant' anagrammed gives 'CONTRASTS'.
Can you help me to learn more?
(Other definitions for contrasts that I've seen before include "Shows differences" , "Dissimilarities of things that are compared" .)