Ptosis (from the Greek word πτῶσις "falling, a fall") refers to droopiness of a body part. Specifically, it can refer to:
- Ptosis (eyelid) (the most common usage of the term), a drooping of the upper or lower eyelid
- Ptosis (breasts), refers to drooping or sagging of the breast. Breast ptosis is related to the laxity of the superficial fascia, suspensory ligaments and skin
- Enteroptosis (intestine), a prolapse or a sinking of the abdominal viscera (internal organs) below their natural position
- Gastroptosis (stomach), the abnormal downward displacement of the stomach. It is not a life threatening condition. The condition frequently causes digestive symptoms and constipation, and is much more prominent in women than men
- Nephroptosis or renal ptosis (kidney)
- Visceroptosis (internal organs), a prolapse or a sinking of the abdominal viscera (internal organs) below their natural position