出典:Wiktionary
From New Latin, from Ancient Greek θηλή (thēlḗ, “nipple”) + New Latin -ion, a diminutive suffix.
This word seems to have had very limited usage, and appears to only be documented in Webster's Third NID. It is not in current usage in the medical field, where the Latin word papilla is the standard term.
Webster's Third New International Dictionary, 1961
a lion
a lioness
the lion rampant
きおいじし.
the lion of the day
the lion of the day
the hornet
the stork
a lion-cub
the chameleon
the panther
the salamander