opistho-comb. form

Etymology: < ancient Greek ὀπισθο-, combining form (in e.g. ὀπισθόδομος opisthodomos n.) of ὄπισθεν behind (see note). Compare classical and scientific Latin opistho-, French opistho-, †opisto- (formations in which are found from at least the early 19th cent.), German opistho-.Ancient Greek ὄπισθεν is < ὀπι- (compare Mycenaean Greek o-pi ), < the same Indo-European base as classical Latin ob (see ob- prefix), and, from a different ablaut grade, ancient Greek ἐπί (see epi- prefix) + -θεν , suffix forming adverbs indicating motion from. The -σ- is perhaps on the analogy of πρόσθεν and ὀπίσω (see opisometer n.). Attested earliest in loans from Greek, directly (as opisthodomos n., opisthotonic adj.), and via classical and post-classical Latin (as opisthotonos n., opisthotonic n.) and French (as opisthograph n.). Earliest in the late 14th cent. in opisthotonos n. Loans and adaptations of scientific Latin and French words especially common in the 19th cent., especially in scientific and technical registers. Formations in English are found from the early 19th cent., especially in the registers detailed above. Combines with second elements ultimately of Greek origin.