Cross from a certain Manchu dynasty (6)
I believe the answer is:
fuming
'cross from a certain' is the definition.
I can't tell whether this definition defines the answer.
'manchu dynasty' is the wordplay.
'manchu' becomes 'fu' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'dynasty' becomes 'ming' (Chinese dynasty).
'fu'+'ming'='FUMING'
Can you help me to learn more?
(Other definitions for fuming that I've seen before include "Livid" , "getting cross" , "Very angry" , "Smoking (with anger?)" , "Smoking with rage" .)