Spell words (5)
I believe the answer is:
terms
'spell words' is the definition.
'terms' can be an answer for 'words' (term is a kind of word). I am not sure about the 'spell' bit.
'spell words' is the wordplay.
'spell' becomes 'term' (I've seen this before).
'words' becomes 's' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'term'+'s'='TERMS'
Can you help me to learn more?
(Other definitions for terms that I've seen before include "Parts of the academic year" , "Conditions; fee" , "Conditions for agreement" , "Work periods" , "words" .)