Crossword Genius

If in need, it could be doubtful (10)

Ross

I believe the answer is:

indefinite

'doubtful' is the definition.
(thesaurus)

'if in need it could be' is the wordplay.
'could be' is an anagram indicator.
'if'+'in'+'need'+'it'='ifinneedit'
'ifinneedit' anagrammed gives 'INDEFINITE'.

(Other definitions for indefinite that I've seen before include "Unsettled" , "Vague" , "Like a" , "sort of article" , "Not decided or not known" .)

I've seen this clue in The Telegraph.
Want a hint initially instead of a full solution? Install my app