Simple past tense and past participle of expatiate.(verb)
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Use "expatiated" in a sentence
"As for Alfred Tennyson Dickens, broken in the depression of the 1890s, a firm of theatrical producers of Melbourne would ultimately organise tours of Britain and America where he read from his father's work and expatiated on his father's life."
"Mr. Perkins, you have previously expatiated at great length on your reasons why you think your preferred style of writing and speaking is the only correct style of writing and speaking."
"Regarding the titles on the BSFA shortlist, I have previously expatiated online, here, here, here and here."