The Americans do not value them very highly (5)
I believe the answer is:
cents
'the americans' is the definition.
Although both the answer and definition are plural nouns, I can't understand how they can define each other.
'do not value them very highly' is the wordplay.
I cannot quite understand how this works, but
'not' could be 'nt' (synonyms) and 'nt' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for cents that I've seen before include "money abroad" , "Fractions of dollar" , "American coins" , "Hundredths of dollar" , "US money, e.g." .)