Current supplier makes a new arrangement for Monday (6)
I believe the answer is:
dynamo
'current supplier' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'a new arrangement for monday' is the wordplay.
'a new arrangement for' indicates anagramming the letters (the letters arranged in a new way).
'monday' is an anagram of 'DYNAMO'.
'makes' acts as a link.
Can you help me to learn more?
(Other definitions for dynamo that I've seen before include "energetic individual" , "Energetic person (colloq.)" , "Power source" , "Live wire" , "Energy converter - hard worker" .)