(Greek: a suffix; inflammation, burning sensation; by extension, disease associated with inflammation)

This suffix has come to mean "inflammation of" but originally it meant "pertaining to" or "of the". The Greek word nosos ["disease"] was either expressed or understood, although it might not be included with the basic element. For example, bursitis nosos would mean "disease of the bursa".

adenitis (s) (noun), adenitises; adenitides (pl)
Inflammation of a lymph node or of a gland: Janet's throat was feeling very sore and hurt, and the doctor diagnosed her as having adenitis, including a swelling of the glands.
adrenalitis (s) (noun) (no pl)
Inflammation of the adrenal gland: Adrenalitis can develop into an insufficiency or inadequacy of aldosterone or even cortisol.
allergic rhinitis (noun), allergic rhinitides (pl)
An inflammatory result in the nasal passages to an allergic stimulus: An allergic rhinitis often includes nose congestion, sneezing, or an itchiness of the mucous membranes.
Inflammation of a blood vessels of the ear. From angi- plus otos, "ear", plus -itis, "inflammation".
Relating to, or affected by pancreatitis or inflammation of the veins in the pancreas.
appendicitis (s) (noun); appendicitises, appendicitides (pl)
Inflammation of the appendix, the small worm-like projection from the first part of the colon.

Appendicitis usually involves infection of the appendix by bacteria that invade it and infect the wall of the appendix. Appendicitis can progress to produce an abscess (a pocket of pus) and even peritonitis (inflammation of the lining of the abdomen and pelvis).

arachnitis (s) (noun) (no pl)
Inflammation of the arachnoid membrane: Arachnitis is a neuropathic disease causing a redness, swelling, and painfulness when the membrane protecting the brain and spinal cord is infected.
arachnoid villi (pl) (noun)
In anatomy, numerous microscopic projections of the arachnoid membrane into some venous sinuses: Arachnoid villi refers to the minute hairlike projections, or tiny finger-like or vascular projections, on the mucous membranes.

arachnoiditis, arachnitis (s) (noun) (no pl)
Inflammation of the arachnoid membrane: Arachnoiditis can be any process of acute, subacute, or chronic inflammation, scarring, proliferative orgranulomatous process in the arachnoid membrane, whether primary or secondary, whether isolated or associated with damage to contiguous nervous tissues.

Types of arachnoiditis, designated according to their situation, include optochiasmatic, basal, spinal, and many other forms.

arthritis (s) (noun), arthritides (pl)
A medical condition characterized by the inflammation of connecting bone areas; usually, accompanied by pain, swelling, and, often, changes in structures: Lance was relieved to hear from Dr. Smith that his arthritis could be relieved with a good diet and prescribed exercises which would help to relieve the inflammation of the structures between the bones.
blepharitis (s), plepharitides (pl)
Inflammation of the eyelids characterized by redness and swelling and dried crusts: "Blepharitis can exist in two forms, anterior and posterior."

"Anterior blepharitis affects the outside front of the eyelid, where the eyelashes are attached. The two most common causes of anterior blepharitis are bacteria (Staphylococcus) and scalp dandruff."

"Posterior blepharitis affects the inner eyelid (the moist part that makes contact with the eye) and is caused by problems with the oil (meibomian) glands in this part of the eyelid."

"Two skin disorders can cause this form of blepharitis: rosacea and seborrheic dermatitis of the scalp (scalp dandruff)."

—Compiled from information located in
Webster's New World Medical Dictionary, Third Edition; Wiley Publishing, Inc.; 2008; page 49.