Goes slowly, like a number of politicians (5)
I believe the answer is:
limps
'goes slowly' is the definition.
Although both the answer and definition are verbs in their -s form, I can't understand how one could define the other.
'number of politicians' is the wordplay.
'number of' becomes 'li' (I can't justify this - if you can you should believe this answer much more).
'politicians' becomes 'MPs' (Members of Parliament).
'li'+'mps'='LIMPS'
'like a' acts as a link.
Can you help me to learn more?
(Other definitions for limps that I've seen before include "Hobbles" , "Walks haltingly" .)