English
exotheca
From exo- + theca (“the calcareous wall of a corallite”).
Formed from exo- + theca ‘the calcareous wall of a corallite’
Proto-Indo-European *h₁eǵʰs ‘out of’
Proto-Hellenic *eks
Ancient Greek ἐκ ‘Out of, from’
Ancient Greek ἔξω ‘outer’
English exo-
Proto-Indo-European *dʰeh₁- ‘to put, place’
Proto-Indo-European *dʰédʰeh₁ti ‘to be putting, placing’
Ancient Greek τίθημι ‘put, set, place’
Ancient Greek θήκη ‘a case, box, receptacle’
Latin thēca ‘a case, envelope, sheath’
English theca
Today it means
noun The tissue that fills the interspaces between the costae of many madreporarian corals, usually consisting of small transverse or oblique septa.
Language periods are conventional ranges, not dates for this word.
Etymograph / exotheca