-nema (pl -nemata) [from Greek nema, nemata thread] Threadlike (pachynema).

-neura [from Greek neuron nerve, sinew, cord] One(s) having nerves or veins of the type indicated by the stem or prefix (Choristoneura).

-nomy [from Greek noma distributing, ordering] Laws of, or knowledge as a whole regarding, a particular field (taxonomy).

-nym [from Greek onoma name] Name (caconym).

-ode or -oid [from Greek -odes, -oeides -like] Shape, form, likeness; usually denotes resemblance (nematode).

-odon [from Greek odous something pointed; tooth, spike] In taxonomic names: One(s) having teeth of the sort indicated by the stem or prefix (Diodon).

-odont [from Greek odous something pointed; tooth, spike] Having teeth of the sort indicated by the stem or prefix (megadont).

-odontia [from Greek odous something pointed; tooth, spike] Condition of having teeth of the sort indicated by the stem or prefix (macrodontia).

-odus [from Greek odous something pointed; tooth, spike] Indicates an animal with teeth of the sort indicated by the stem or prefix (Ceratodus).

-odynia See: -dynia.

-oesophageal See: -esophageal.

-oid [from Greek -odes, -oeides -like] Denotes resemblance (nevoid).

-oida or -odea or -oidei [from Greek -odes, -oeides -like] Animals of the type indicated by the stem or prefix (Ganoidea, Anguilloidei).

-ole [from Latin -olus, -ola, -olum diminutive suffixes] Diminutive, indicating small size (arteriole).

-ologia or -ology See: -logia, -logy.

-oma (pl -omas, -omata) [Greek -oma, -omata] Swelling, tumor (carcinoma, sarcoma).

-omphalos or -omphalus [from Greek omphalos navel, umbilical cord] (1) condition of the navel (acromplalus); (2) condition of the umbilical cord (exomphalos).

-on [neuter form of Greek -os] (1) basic genetic element (operon, cistron); (2) inert gas (argon).

-ont [from Greek on being (pres. participle of einein)] Living being, cell, organism (gamont).

-onychia or -onyxis [from Greek onyx talon, claw] Condition of the fingernails or toenails of the type indicated by the stem or prefix (brachyonychia).

-onychium [from Greek onyx talon, claw] A region of, or one having fingernails or toenails, of the type indicated by the stem or prefix (hyponychium).

-onym [from Greek onoma name] Name (caconym).

-opthalmos [from Greek ophthalmos eye] Having eyes of the type, or having a condition of the eyes of the type, indicated by the stem or prefix (exophthalmos).

-opia or -opsia or -opy [from Greek ops eye, face] (1) vision or condition of vision of the type indicated by the stem or prefix (myopia); (2) having eyes of the type, or having a disease of the type, indicated by the prefix (erythropia).

-ops [from Greek ops eye, face] One having the type of eyes or face indicated by the stem or prefix (Tursiops).

-or [from Latin -or] One who, that which (repressor).

-orchidism [from Greek orchis testicle] Condition of the testicle indicated by the stem or prefix (macroorchidism).

-orexia [from Greek orexis desire, appetite] Appetite (anorexia).

-orexic [from Greek orexis desire, appetite] Denotes the condition of appetite indicated by the stem or prefix (anorexic).

-ornis (pl ornithes) [from Greek ornis bird] In taxonomic names: bird of the type indicated by the stem or prefix (Agapornis). See also: -cornis.

-ory [Latin -orius] Belonging to, connected with (laboratory).

-osis [Greek -osis] (1) condition, disease, action; typically denotes production or increase (halitosis); (2) invasion or increase of parasites within an organism (trichinosis).

-ostosis [from Greek osteon bone + -osis] (1) bony growth of the type indicated by the stem or prefix (hyperostosis); (2) formation of an osseous tumor of the type indicated by the stem or prefix (endostosis).

-ostraca [from Greek ostrakon shell] In taxonomic names (usually of crustaceans): shell, shelled (Leptostraca).

-otic [from Greek -otikos] (1) of or relating to the thing indicated by the stem or prefix (biotic); (2) of or relating to the ear or a part of the ear (diotic).

-ous [from Latin -us] Abounding in, having, possessing (filamentous).