solidity n. + Add to list US //səˈɫɪdəti// UK //səlˈɪdɪti// so·lid·i·ty SynonymsAntonymsEtymology Synonyms solidness Antonyms hollownessporosityOriginLATsoliditās→FRMsolidité→ENsolidity From solid + -ity, from Middle French solidité, from Latin soliditās.