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.
1 First Quarter is when half of the waxing or growing moon is visible because the Sun is shining only on half of the hemisphere that is visible from Earth.  Full Moon is when the moon appears to be a complete circle because the Sun is shining directly on the entire visible hemisphere.