Speculator initially tense — gold pinched in robbery (8)
I believe the answer is:
theorist
'speculator' is the definition.
(I've seen this before)
'initially tense gold pinched in robbery' is the wordplay.
I cannot quite see how this works, but
'initially' could be 'ist' (ist resembles 1st) and 'ist' is found within the answer.
'tense' could be 't' (grammatical abbreviation) and 't' is located in the answer.
'gold' could be 'or' ('or' is the heraldic name for gold) and 'or' is located in the answer.
The remaining letters 'he' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for theorist that I've seen before include "Creator of hypothesis" , "Expert in established hypotheses" , "Speculator" , "Thinker" , "Abstract reasoner" .)