A Grammatical Dictionary of Botanical Latin

-thele,-es (s.f.I): in Gk. comp. nipple [> Gk. thElE (s.f.I), papilla, mammilla, nipple; ‘the part of the breast which gives suck, the teat, nipple; papilla]; see First Declension.

On analogy with raphE,-Es (s.f.I):

     singular     plural      thēlē,- ēs (s.f.I), nipple.
Nom.	thēlē	      thēlae
Gen.	thēlēs	thēlārum
Dat.	thēlae      thēlis
Acc.	thēlēn	thēlās
Abl.	thēlē 	thēlis

NOTE: not to be confused with thely-, thelys-, q.v., ‘woman.’

NOTE: the classical definition is ‘nipple’ but in botanical terms in (areolate) surface morphology, ‘thele’ may be translated variously according to size and shape, as wart, pimple, papilla, tumor-, tubercle, verruca, protuberance, elevation, bump. Often there is a central opening on the areole.

Thele, in Cactaceae, mostly refers to protuberances of various kinds that cover the cactus stem or rib ridges, often called ‘tubercles.’ They are declined as nouns according to the above paradigm. Thele is a feminine noun and e.g. Cactus is masculine (Cactus macrothele; Parodia,-ae (s.f.I) microthele; Polytrichum,-i (s.n.II) leptothele).

‘tubercle’ will be used in the following list:

aulacothele, with a grooved tubercle; conothele, with conic tubercles; helicothele, with spirally arranged tubercles; ianothele, the globose fruit is rose-red or rosy violet [Rhipsalis]; lophothele, with crested tubercles; macrothele, with large tubercles; microthele, with little tubercles; oothele, with egg-shaped tubercles; pachythele, with stout or thick tubercles; pheumatothele, with wart- or tumore-like tubercles; polythele, with many tubercles.

A binomial declined:

Cactus,-i (s.m.II) macrothele,-es (s.f.I)

             singular                     plural     
Nom. Cactus  macrothele     Cacti macrothelae
Gen.  Cacti   macrotheles     Cactorum macrothelarum
Dat.  Cacto   macrothelae    Cactis macrothelis
Acc.  Cactum  macrothelem  Cactos macrothelas
Abl.   Cacto   macrothele      Cactis macrothelis

[Angler-fish] Bufoceratias thele; the ‘nipple’ is the terminal papilla of the esca, or the fleshy bait at the tip of the illicium, i.e. of the ‘fishing rod’ horn-like projection of the head [Bufocertias,-ae (s.m.I), abl.sg. Bufoceratia [published as masc.]

[lichen] Staurothele (Verrucariaceae) rock pimples, wart lichens: saxicolous, crustose lichens, the (bullate-) (radiate-) areolate crusts with perithecia one per areole.

Polytrichum leptothele (Polytrichaceae); Stelis dithele (Orchidaceae); Trichosalpinx dithele (Orchidaceae)