Possible Clues:

• Transparent covering of outer eyeball
• One car damaged part of the eye
• Situation that's tricky, not right, with a part of the eye
• Eye part of the maize cob, you'll hear
• It's under the conjunctiva
• It sounds more of a chestnut, but it's not all my eye
• Eye site?
• The grain begins not be all my eye
• Membrane that could be seen in one arc
• Old jokes perhaps, each one seen through by pupil