image > effigy, statue, idol

5 Of massy gold, which with its own light shone;

massy > solid

6 And wings it had with sundry colours dight,

dight > arrayed

7 More sundry colours than the proud pavone

pavone > peacock (Italian word)

8 Bears in his boasted fan, or Iris bright,

Iris > (Goddess of the rainbow. See GL 16.24) bright > beautiful (sparing the duplication of the rhyme in line 9)

9 When her discoloured bow she spreads through heaven bright.