'phakic' originates from Modern Latin/Neo-Latin, ultimately from the Greek word 'phakos', where the root 'phak-' meant 'lens' or 'lentil', and the suffix '-ic' meant 'pertaining to'.

'phakic' changed from Neo-Latin/medical Latin usages such as 'phakicus' or Greek 'phakikos' and entered modern English through scientific and medical Latin terminology as 'phakic'.

Initially it meant 'pertaining to the lens' and over time became specialized in ophthalmology to mean 'having a natural crystalline lens (of the eye)'.