In the original Greek it's eikon. if you're really Greek, you should know that is word has a much deeper meaning the the English word "image".
“Arius agrees with early Christian conclusions that God the Father is necessarily uncreated and un- begotten, and yet, because the Son is created and begotten, as he finds in the words of Colossians 1, the Son cannot truly be God … Arius’s theology is not based on a new understanding of Colossians 1:15, but rather builds on how this same passage had already been used by early Christian writers. … The problem with Colossians 1:15 is that the Arians’ interpretation of this passage to defend Christ as creature and not fully divine is entirely plausible, and the problem for Athanasius and his sympathizers is that the basic sense of Colossians 1:15 leads to Arianism.”
Jennifer Strawbridge, ‘The Image and Unity of God: The Role of Colossians I in Theological Controversy’, in The Bible and Early Trinitarian Theology, Ed. Christopher A. Beeley and Mark E. Weedman (2018), pages 188 and 189.