Account shortened by American money - this may be grave! (6)
I believe the answer is:
accent
'this may be grave' is the definition.
(grave accent is a type of accent mark)
'account shortened by american money' is the wordplay.
'account' becomes 'acc'.
'shortened' means to remove the last letter.
'by' is a charade indicator (letters next to each other).
'american money' becomes 'cent' (eg denomination of dollars. I am not sure about the 'american' bit.).
'acc' with its last letter taken away is 'ac'.
'ac'+'cent'='ACCENT'
Can you help me to learn more?
(Other definitions for accent that I've seen before include "It could be acute" , "A diacritic mark" , "Distinctive way of pronouncing words" , "Underline" , "Speech inflection" .)