Ideas, however terrible, suffice at first (8)
I believe the answer is:
thoughts
'ideas' is the definition.
('thought' can be a synonym of 'idea')
'however terrible suffice at first' is the wordplay.
'however' becomes 'though' ('though' can be a synonym of 'however'**).
'at first' indicates taking the first letters.
The first letters of 'terrible suffice' is 'ts'.
'though'+'ts'='THOUGHTS'
(Other definitions for thoughts that I've seen before include "Ideas, reflections" , "Cogitations" , "They are in my mind" , "Notions" , "Ideas and opinions (8)" .)