Value of American English (3)
I believe the answer is:
use
'value' is the definition.
(I've seen this before)
'american english' is the wordplay.
'american' becomes 'us'.
'english' becomes 'e' (abbreviation).
'us'+'e'='USE'
'of' is the link.
(Other definitions for use that I've seen before include "particular church liturgy" , "consume; exploit" , "Put into service, do something with" , "Put to work" , "Milk" .)