- indicating a process or state: metamorphosis
- indicating a diseased condition: tuberculosis
Compare -iasis - indicating the formation or development of something: fibrosis
WordReference Random House Unabridged Dictionary of American English © 2026
-osis,
- a suffix occurring in nouns that denote actions, conditions, or states (hypnosis;
leukocytosis;
osmosis), esp. disorders or abnormal states (chlorosis;
neurofibromatosis;
tuberculosis). Cf. -otic.
- on the model of Greek borrowings ending in Greek -ōsis, as sklērōsis sclerosis, derived origin, originally from verbs ending in the formative -o- (-ō- in noun, nominal derivatives), with the suffix -sis -sis
Collins Concise English Dictionary © HarperCollins Publishers::
-osis suffix forming nouns
'-osis' also found in these entries (note: many are not synonyms or translations):
-biosis
- byssinosis
- chlorosis
- cirrhosis
- -iasis
- leptospirosis
- miosis
- osteoporosis
- psittacosis
- psychosis
- sarcomatosis
- tuberculosis
- acanthocytosis
- acidosis
- actinobacillosis
- actinomycosis
- adenosis
- agranulocytosis
- alkalosis
- amaurosis
- amphiarthrosis
- amyloidosis
- anaplasmosis
- anastomosis
- anastylosis
- ankylosis
- anthracosis
- apotheosis
- arthrosis
- asbestosis
- aspergillosis
- ateliosis
- athetosis
- avitaminosis
- babesiosis
- berylliosis
- biocenology
- brucellosis
- calcinosis
- carcinomatosis
- coccidiosis
- cryptococcosis
- cyanosis
- cyclosis
- cyrtosis
- cysticercosis
- dermatosis
- distomatosis
- diverticulosis
- ecchymosis