Egyptian goddess is seen repeatedly (4)
I believe the answer is:
isis
'egyptian goddess' is the definition.
(I've seen this before)
'seen repeatedly' is the wordplay.
'seen' becomes 'is' (I can't justify this - if you can you should give a lot more credence to this answer).
'repeatedly' says to double the letters.
'is' duplicated is 'ISIS'.
'is' is the link.
Can you help me to learn more?
(Other definitions for isis that I've seen before include "Jihadists" , "The goddess lives twice" , "Si, si - an Egyptian goddess" , "River Thames at Oxford" , "Mrs Osiris" .)