Gathered together with the aim of blocking repellent symbol (5)
I believe the answer is:
totem
'symbol' is the definition.
(I've seen this before)
'gathered together with the aim of blocking repellent' is the wordplay.
I cannot really see how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is present in the answer.
'of' could be 'o' and 'o' is located in the answer.
The remaining letters 'tem' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for totem that I've seen before include "Object of veneration" , "something sacred" , "symbol of spiritual significance" , "Image representing tribe" , "Natural thing adopted as an emblem" .)