Endless damage to legal term
I believe the answer is:
de facto
'endless' is the definition.
Both the definition and answer are adjectives. Perhaps you can see a link between them that I can't see?
'damage to legal term' is the wordplay.
I cannot really understand how this works, but
'to' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for de facto that I've seen before include "Actual, not legal (situation)" , "actually" , "In practice" , "In fact (Latin)" , "In reality, actual" .)