-itis

From New Latin -itis, from Ancient Greek -ῖτις (-îtis, “pertaining to”). This is the feminine form of adjectival suffix -ίτης (-ítēs) because it was used with the feminine noun νόσος (nósos, “disease”), particularly with ἀρθρῖτις (νόσος) (arthrîtis (nósos), “disease of the joints”) (one of the earliest English borrowings from which the suffix was extracted and abstracted).[1] Humorous sense by generalization.

• IPA^(key): /-ˈaɪtɪs/

-itis (usually uncountable, sometimes -itides or rarely -itises)

1. (pathology) Suffix denoting diseases characterized by inflammation, itself often caused by an infection.
2. (humorous) Used to form the names of various fictitious afflictions or diseases.
   • What to Do About Senioritis: Make Your Senior Year Count, College Board. Accessed April 4, 2008.[2]

While most of the derived terms theoretically have plurals in -itides (from the Ancient Greek -ῑ́τῐδες (-ī́tides), plural of -ῖτῐς (-îtis)), -itises (the regularized English plural), or both, these forms are rarely used, as the derived terms are mass nouns, so their plurals are called for only when referring to types. For example, hepatitides or hepatitises as "types of hepatitis" have some currency in the medical literature, but most other such plurals do not.

• itis

• English dictionary of medical terms

• IIST, IITs, SITI, is it

From New Latin -ītis, from Ancient Greek -ῖτις (-îtis).

-itis f (plural -itis)

1. (pathology) -itis

• “-itis” in Diccionari de la llengua catalana, segona edició, Institut d’Estudis Catalans.
• “-itis” in Gran Diccionari de la Llengua Catalana, Grup Enciclopèdia Catalana.
• “-itis” in Diccionari normatiu valencià, Acadèmia Valenciana de la Llengua.

From Ancient Greek -ῖτις (-îtis, “pertaining to”).

• (Classical) IPA^(key): /ˈiː.tis/, [ˈiː.tɪs]

-ītis f (genitive -ītidis); third declension

1. (New Latin, pathology) -itis (suffix denoting diseases characterized by inflammation, itself often caused by an infection)

Third declension.

See -ītēs.

• (Classical) IPA^(key): /ˈiː.tiːs/

-ītīs

1. dative plural of -ītēs
2. ablative plural of -ītēs

From New Latin -itis, from Ancient Greek -ῖτις (-îtis, “pertaining to”).

-itis

1. (pathology) -itis (suffix denoting diseases characterized by inflammation, itself often caused by an infection)
2. (humorous) -itis (used to form the names of various fictitious afflictions or diseases)

• “-itis” in Diccionario de la lengua española, Vigésima tercera edición, Real Academia Española, 2014.