Superfluous spears destroyed (6)
I believe the answer is:
sparse
'superfluous' is the definition.
Both the answer and definition are adjectives. Perhaps there's an association between them I don't understand?
'spears destroyed' is the wordplay.
'destroyed' indicates an anagram.
'spears' anagrammed gives 'SPARSE'.
Can you help me to learn more?
(Other definitions for sparse that I've seen before include "Thinly populated" , "not packed together" , "Thinly dispersed" , "Thinly-spread" , "Thinly dotted about" .)