Ectropion (Outward turning of the eyelid) is most commonly seen in the lower eyelid. It does occur in the upper eyelid, though that is very rare. I will be referring to lower eyelid ectropion below.
Entropion (in turning of the eyelid) is most commonly seen in the lower eyelid. It does occur in the upper eyelid, though that is very rare. I will be referring to lower eyelid entropion below.
Ptosis is a droopy eyelid. In adults the most common reason for ptosis is slippage of the levator muscle of the eyelid from the tarsal plate (the firm cartilage like plate of the upper eyelid).