Ob-scurity
From our UK edition
The back-page notebook in the Times Literary Supplement the other week was pondering whether the word obnixely had ever really been used. It means ‘earnestly, strenuously’, but I can see that there is not much point using it if no one knows what it means. The prefix ob- generates a goodly store of seldom used words: obacerate (‘to stop the mouth’); obcaecate (‘blind, uncomprehending’); obganiate (‘to be tediously repetitious’); obstupely (‘dully’) and the splendid obeliscolychny (‘lighthouse’).