Explorer appreciated source of medicine in medical facility (6)
I believe the answer is:
tasman
'explorer' is the definition.
(17th-century explorer Abel Tasman)
'appreciated source of medicine in medical facility' is the wordplay.
'appreciated' becomes 'ta' (I've seen this in other clues).
'source of' indicates taking the first letters.
'in' is an insertion indicator.
'medical facility' becomes 'san' (I can't explain this - if you can you should give a lot more credence to this answer).
The first letter of 'medicine' is 'm'.
'm' placed into 'san' is 'sman'.
'ta'+'sman'='TASMAN'
Can you help me to learn more?
(Other definitions for tasman that I've seen before include "Sea named after Dutch navigator" , "Dutch antipodean explorer" , "Dutch sailor" , "Abel --, Dutch navigator" , "explored Pacific" .)