Unpleasant type of animal seen by river (6)
I believe the answer is:
rotter
'unpleasant type' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe there's an association between them I don't understand?
'animal seen by river' is the wordplay.
'animal' becomes 'otter' (I've seen this before).
'seen by' says to put letters next to each other.
'river' becomes 'r' (abbreviation for river).
'otter' put after 'r' is 'ROTTER'.
'of' is the link.
Can you help me to learn more?
(Other definitions for rotter that I've seen before include "Absolute bounder" , "Bad lot" , "One not to be honoured" , "Bad guy" , "Scoundrel" .)