ohlon

diphthong

ohlon (pl. ohloni is attested) noun "diphthong", used of both vocalic diphthongs and "consonantal diphthongs" like mb(VT39:9)

ohlon

noun. diphthong

ocamna

diphthong

ocamna ("k")noun "diphthong" (VT44:13)

osamnar

diphthong

osamnar, noun a word for "diphthong" (actually plural "diphthongs", sg. #osamna?) which Tolkien in the late thirties (?) replaced by ocamna, q.v.