Antonyms for improvement. 5 synonyms of improvement from the Merriam-Webster Thesaurus, plus 34 related words, definitions, and antonyms. What is the opposite of Improve? 26 synonyms of enhance from the Merriam-Webster Thesaurus, plus 58 related words, definitions, and antonyms. Antonyms for Improve (opposite of Improve). Find more ways to say better, along with related words, antonyms and example phrases at Thesaurus.com, the world's most trusted free thesaurus. Another word for better. Antonyms for improve. 1 antonym for improved: unimproved. Antonyms for improve include impair, deteriorate, ruin, diminish, disimprove, decrease, hinder, recede, reduce and lessen. See more. These antonyms of the word improve are provided for information only. Synonyms for improve in Free Thesaurus. Find another word for enhance. Find more opposite words at wordhippo.com! Find another word for developed. Synonyms-thesaurus.com is more than 70,800 synonyms and 47,200 antonyms available. Find another word for improvement. Synonyms for improvement in Free Thesaurus. Find more ways to say improved, along with related words, antonyms and example phrases at Thesaurus.com, the world's most trusted free thesaurus. Antonyms for improved. 34 synonyms of developed from the Merriam-Webster Thesaurus, plus 118 related words, definitions, and antonyms. Another word for improved. Improvement: an instance of notable progress in the development of knowledge, technology, or skill. Fast is an antonym of slow. Here you use the antonyms for improve. Antonym definition, a word opposite in meaning to another. What are synonyms for improved? Synonyms for improved in Free Thesaurus.