You use solid to describe something such as the basis for a policy or support for an organization when it is strong, because it has been developed carefullySynonyms: firm, united, unanimous, consistent More Synonyms of solidadverb [ADVERB with verb] This district is Republican.So far, majority public opinion is behind the government.Her form on an easy surface is solid. The Sun (2008)She faced intense pressure to plead guilty despite a lack of solid evidence. Christianity Today (2000)There is also something solid…