Term wasted with eel that's prone to disease (3,4)

I believe the answer is:

elm-tree

'that's prone to disease' is the definition.
(elms are often affected by Dutch Elm Disease)

'term wasted with eel' is the wordplay.
'wasted with' indicates an anagram.
'term' with its letters mixed up with 'eel' gives 'ELM-TREE'.

(Another definition for elm-tree that I've seen is " Victim of Dutch disease".)

I've seen this clue in The Guardian.

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