Likeness, or contrast (10)
I believe the answer is:
comparison
I believe this clue is a double definition.
'likeness' is the first definition.
(I know that comparison is a type of likeness)
'contrast' is the second definition.
(I've seen this before)
(Other definitions for comparison that I've seen before include "distinction" , "In contrast" , "Similarity" , "Assessment of differences" , "Analogy; likeness" .)