-rachidia [from Greek rachis spine] Denotes a condition of the spine of the kind indicated by the stem or prefix (atelorachidia) — usually refers to the vertebral column, but can also refer to a spine of any kind, as the spine of a leaf.

-rhine or -rrhine [from Greek rhis nose or snout] One having a nose or snout of the sort indicated by the stem or prefix (catarrhine).

-rhiza or -rrhiza [from Greek rhiza root] Root; like or connected to a root (Cotylorhiza tuberculata).

-rrhage or -rrhagia [from Greek rhegnumi to break asunder, rend] Excessive or abnormal flow or outflow (hemorrhage).

-rrhaphy [from Greek rhaphe stitching, sewing] Suturing or stitching (angiorrhaphy).

-rrhea (British: -rrhoea) [from Greek rein flow] Denotes a flow or outflow (dacryorrhea).

-rrhexis [from Greek rhegma a breakage or fracture] Rupture, splitting (ovariorrhexis).

-rrhine See: -rhine.

-rrhiza See: -rhiza.

-sarc [from Greek sarx flesh] Flesh, soft tissue (ectosarc, endosarc).

-saur or -saura or -sauria or -saurus [from Greek saura lizard] Lizard; animals like lizards (dinosaur).

-schisis [from Greek schizein to split or cleave] Fissure, breaking up (gastroschisis).

-sclerosis [from Greek skleros hard] Drying, hardness (arteriosclerosis).

-scope [from Greek skopein to examine] A means for viewing (microscope).

-scopy [from Greek skopein to examine] Seeing, visual examination of the type indicated by the stem or prefix (microscopy).

-setose or -setous [from Latin saeta hair, bristle] Having bristles of the type or number indicated by the stem or prefix (bisetose).

-sion See: -ion.

-sis [from Greek -sis an ending indicating a state or condition] Denotes a condition. See: -iasis, -osis, -basia/-basis, -biosis, -clasia/-clasis, -genesis, -gnosis, -kinesis, -stasia/-stasis, -stomosis.

-soma (pl -somata) [from Greek soma body] In taxonomic names: one(s) having a body (or region of a body) of the type indicated by the stem or prefix (Trypanosoma).

-some [from Greek soma body] (1) chromosome; (2) region of a body; (3) a body of the type indicated by the root or prefix (liposome, lysosome, melanosome).

-spasm [from Greek spasmos convulsion] Twitching, or involuntary contraction, of the thing indicated by the stem or prefix (chirospasm).

-sperma or -spermum [from Greek sperma seed, semen, race, origin] In taxonomic names: one(s) having seeds of a certain type or number (Pterospermum).

-spermal or -spermous [from Greek sperma seed, semen, race, origin] Having seeds of the type or number indicated by the stem or prefix (tetraspermous).

-spermy (pl spermies) [from Greek sperma seed, semen, race, origin] Having seeds of a certain type or number (polyspermy).

-spora [from Greek sporos sowing, seed, offspring, semen] In taxonomic names: Having spores of the type indicated by the stem or prefix (Neurospora).

-spore [from Greek sporos sowing, seed, offspring, semen] Seed, spore (ascospore).

-sporic (also -sporous) [from Greek sporos sowing, seed, offspring, semen] Having spores of the type or number indicated by the stem or prefix (ascosporic).

-sporium [from Greek sporos sowing, seed, offspring, semen] (1) layer of a spore wall (exosporium); (2) in taxonomic names: Having spores of the type indicated by the stem or prefix (Cladosporium).

-spory (pl -spories) [from Greek sporos sowing, seed, offspring, semen] Condition of having spores of the type or number indicated by the stem or prefix (heterospory).

-stasia or -stasis [from Greek stasis condition of standing] (1) slowing, stoppage; (2) inhibition of growth (homeostasis); (3) a condition while standing of the sort indicated by the stem or prefix (astasia).

-stat [from Greek -states something causing stasis] (1) tool for keeping something stable or controlled (hemostat); (2) agent inhibiting growth (bacteriostat).

-stemonous [from Greek stemon warp, thread] Having stamens of the type indicated by the stem or prefix (diplostemonous).

-stomate or -stomatous [from Greek stoma, stomat- mouth] Having a mouth of the type indicated by the stem or prefix (cyclostomate).

-stome [from Greek stoma, stomat- mouth] One with a mouth of the sort indicated by the stem or prefix (deuterostome).

-stomosis or -stomy [from Greek stoma, stomat- mouth] To provide with an outlet (anastomosis).