Eucalyptus to ground, our highest faller (7,5)

I believe the answer is:

cautley spout

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'our highest faller' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'eucalyptus to ground' is the wordplay.
'ground' indicates an anagram ('grind' the letters into a new form).
'eucalyptus'+'to'='eucalyptusto'
'eucalyptusto' with letters rearranged gives 'CAUTLEY SPOUT'.

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