Animals seen initially by Dickensian villain (5)
I believe the answer is:
sheep
'animals' is the definition.
(I have seen 'Woolly animals ' mean 'sheep' so perhaps 'animals' could also mean 'sheep')
'seen initially by dickensian villain' is the wordplay.
'initially' indicates taking the first letters.
'by' means one lot of letters go next to another.
'dickensian villain' becomes 'heep' (Uriah Heep, villain in Dickens' David Copperfield).
The initial letter of 'seen' is 's'.
's'+'heep'='SHEEP'
(Other definitions for sheep that I've seen before include "Farm animals" , "Animals said to lack initiative" , "Ruminant animal" , "Members of congregation" , "Ovine animals" .)