Final answer:
The proper dermatological term for the flat elevation of the skin on the left upper lid is plaque.
Step-by-step explanation:
The proper dermatological term for the flat elevation of the skin on the left upper lid of your 73-year-old male patient is plaque.
A plaque is a large, raised, and flat area on the skin that measures more than 1 cm in diameter. It can have an irregular shape and may be different in color compared to the surrounding skin.
In this case, the flat elevation on the left upper lid fits the description of a plaque.