1780S Antonyms There are 2 antonyms of the abbr 1780s. (opposite meanings)Did you mean?Definition of 1780SBest Opposite Words For 1780STop 20Top 10 Top 20 (Default)Top 50 Top 100 All All (Default)WordsPhrases All All (Default)Verb Noun Adjective Adverb Expand?WordSave?Synonyms..UsageType1770snounnnoun • the decade from 1770 to 17791790snoun, adjectiven, adjnoun • the decade from 1790 to 1799