Get along with Dudley, lacking class (5)
I believe the answer is:
seedy
'get along with dudley lacking class' is the definition.
I can't tell whether this defines the answer.
'get along with dudley' is the wordplay.
'get' becomes 'see' (both can mean to understand).
'along with' is a charade indicator (letters next to each other).
'dudley' becomes 'dy' (I can't justify this - if you can you should give a lot more credence to this answer).
'see'+'dy'='SEEDY'
Can you help me to learn more?
(Other definitions for seedy that I've seen before include "Unseemly" , "Raspberry jam might be" , "Pip is" , "Sleazy, sordid" , "sickly" .)