-clasecomb. form

Primary stress is retained by the usual stressed syllable of the preceding element and vowels may be reduced accordingly.
Origin: A borrowing from French; frequently modelled on German lexical items. Etymon: French -clase.
Etymology:  <  French -clase (in e.g. euclase  euclase n.;  <  ancient Greek κλάσις   action of breaking, fracture  <  κλᾶν   to break (see clastic adj.) + -σις  -sis suffix), frequently after formations in German -klas (in e.g. Oligoklas  oligoclase n., Orthoklas  orthoclase n.). Compare Italian -clasia   (in e.g. periclasia  periclase n.).Formations after foreign-language (originally French, but most frequently German) models are found from at least the beginning of the 19th cent. (e.g. euclase n., oligoclase n., periclase n.). Formations within English are attested from at least the middle of the 19th cent. (e.g. clinoclase n. at clino- comb. form 1, scleroclase n.).
This is a new entry (OED Third Edition, November 2010; most recently modified version published online March 2022).