Blepharitis, or eyelid inflammation, one of the most common problems, is characterized by erythematous eyelids with accumulation of debris along the eyelid margin. Malignant eyelid tumors may be associated with lash loss and erosion of normal eyelid structures.
Quarter Moon, captured by NASA astronauts. Image credit: NASA. You can have a first quarter moon, when the Moon is halfway between a new moon and full moon. A new moon occurs when the Moon is directly in between the Sun and the Earth. From that perspective, the illuminated Moon is facing away from the Earth.
In between these four instantaneous phases, the moon is said to be in four transitional phases, which each last slightly more than a week. Waxing crescent comes after new moon, waxing gibbous follows first quarter, waning gibbous comes after full moon and waning crescent follows last quarter. A waxing moon is getting larger while a waning moon is shrinking. Most people are familiar with a crescent shape, but the word gibbous is not normally in most people's vocabulary. It is from a Middle English word for hump-backed but can also refer to a pregnant belly.