As-salamu alaykum
'Zurq' in Arabic is the plural of 'azraq' which implies the blueness or greyness in the eye, something outside of the state of being 'normal' eyes from the perspective of the ancient Arabs. This can also imply blindness. Hence, it is at times rendered as blue-eyed / white-eyed and in the context of the verse, characterised by the onset of fear or terror.
The term also carries the nuance of looking at something sharply, attentively or intently. This latter interpretation is arguably also in keeping with the fact that on the Day of Judgement, everything will be made clear - One's eyesight will not be confounded with the illusions of the world. Matters will become crystal clear. This is also supported by the following verse:
050:022
"Certainly you were heedless of it, but now We have removed from you your veil / cover, so your sight today is sharp."
I hope this helps, God willing
Joseph