Portentous doctor lifted one with commonsense (7)
I believe the answer is:
ominous
'portentous' is the definition.
(thesaurus)
'doctor lifted one with commonsense' is the wordplay.
'doctor' becomes 'mo' (medical officer).
'lifted' says the letters should be written in reverse (going up in down clue).
'one' becomes 'i' (Roman numeral).
'with commonsense' becomes 'nous' (I've seen this in other clues).
'mo' written backwards gives 'om'.
'om'+'i'+'nous'='OMINOUS'
(Other definitions for ominous that I've seen before include "Foreboding, threatening" , "Threatening, doesn't look good" , "Threatening, looks bad" , "Threatening, not looking good" , "Boding ill" .)