Ideas (8)
'ideas' is the definition.
(notion is a kind of idea)
This is all the clue.
(Other definitions for notions that I've seen before include "Whims, ideas or small personal articles" , "Fanciful feelings" , "Fanciful or capricious ideas" , "Thoughts" , "Vague ideas" .)
'ideas' is the definition.
('thought' can be a synonym of 'idea')
This is all the clue.
(Other definitions for thoughts that I've seen before include "Cogitations" , "They are in my mind" , "Ideas, musings" , "Notions" , "Ideas and opinions (8)" .)
'ideas' is the definition.
(concept is a kind of idea)
This is all the clue.
(Other definitions for concepts that I've seen before include "'Abstract ideas, thoughts (8)'" , "Abstract or general idea" , "Abstract or general ideas" , "Abstracts or general ideas" .)
(Other definitions for any that I've seen before include "One, no matter which" , "Long-running Radio 4 discussion show" , "At all; in some degree" , "Several" , "One or some, whichever you choose" .)