Chew up a thousand fish (6)
I believe the answer is:
mangle
'chew up' is the definition.
Although both the answer and definition are verbs in their base form, I don't understand how one could define the other.
'a thousand fish' is the wordplay.
'a thousand' becomes 'm' (Roman numeral for a thousand).
'fish' becomes 'angle' (angle can mean to fish).
'm'+'angle'='MANGLE'
Can you help me to learn more?
(Other definitions for mangle that I've seen before include "Old clothes-wringer" , "Severely mutilate" , "Tear up" , "Clothes-wringer for leg-man" , "Squeeze" .)