Held forth given small prod (5)
I believe the answer is:
spoke
'held forth' is the definition.
(I've seen this in another clue)
'given small prod' is the wordplay.
'given' says to put letters next to each other.
'small' becomes 's' (abbreviation - e.g. clothes size).
'prod' becomes 'poke' (synonyms).
's'+'poke' is 'SPOKE'.
(Other definitions for spoke that I've seen before include "Bicycle wheel rod" , "Wheel's radial member" , "Uttered - bicycle wheel part" , "Said something" , "Rung" .)