Doctor operates, implanting new tongue (9)
I believe the answer is:
esperanto
'tongue' is the definition.
(I've seen this before)
'doctor operates implanting new' is the wordplay.
I cannot quite understand how this works, but
'new' could be 'n' (common abbreviation eg NT for New Testament) and 'n' is present in the answer.
an anagram of 'operates' is 'esperato' which is within the left over letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for esperanto that I've seen before include "Parse note in the artificial language" , "largely unknown language" , "Artificial international language devised in 1887" , "composite language" , "A language; neat prose (anag.)" .)