The standard linked with an early invader (6)
I believe the answer is:
norman
'early invader' is the definition.
'norman' can be an answer for 'invader' (as in the Norman Conquest of 1066). I'm not sure about the 'early' bit.
'the standard linked with an' is the wordplay.
'the standard' becomes 'norm' (norm is a kind of standard).
'linked with' means one lot of letters go next to another.
'norm'+'an'='NORMAN'
Can you help me to learn more?
(Other definitions for norman that I've seen before include "French dialect" , "Boy's name" , "Barry, Greg or Jessye" , "Someone who's not British" , "Style of architecture" .)