Command from Lord Erdington (5)
I believe the answer is:
order
'command' is the definition.
(order is a kind of command)
'from lord erdington' is the wordplay.
'from' indicates the answer is hidden within the clue.
'ORDER' can be found hidden inside 'lord erdington'.
(Other definitions for order that I've seen before include "Command; sequence" , "architectural style" , "Directive or society" , "Command; social class" , "It could be the usual" .)