Dogs receiving large decisive blows (8)
I believe the answer is:
settlers
'blows' is the definition.
Although both the answer and definition are plural nouns, I can't understand how they can define each other.
'dogs receiving large decisive' is the wordplay.
'dogs' becomes 'setters' (setter is a kind of dog).
'receiving' means one lot of letters goes inside another.
'large decisive' becomes 'l' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'setters' enclosing 'l' is 'SETTLERS'.
Can you help me to learn more?
(Other definitions for settlers that I've seen before include "Trestles for pioneers" , "Pioneers, homesteaders" , "Immigrants" , "who pay their bills?" , "Colonists" .)