Synonyms: foundation, fundament, groundwork, cornerstone, base, basis. Find more ways to say linchpin, along with related words, antonyms and example phrases at Thesaurus.com, the world's most trusted free thesaurus. Over time a cornerstone became a ceremonial masonry stone, or replica, set in a prominent location on the outside of a building, with an inscription on the stone indicating the construction dates of the building and the names of architect, builder, and other significant individuals.The rite of laying a cornerstone is an important â¦ Another word for cornerstone. 17 synonyms for cornerstone: basis, key, premise, starting â¦ Architectural term used twice in the New Testament ( Eph 2:20; 1 Peter 2:6) to speak of the exalted Jesus as the chief foundation stone of the church, the cornerstone on which all the building depends.The New Testament draws on two Old Testament passages about the coming Messiah ( Isa 28:16; Zech 10:4).In â¦ Synonyms for cornerstone include basis, bedrock, foundation, keystone, base, linchpin, mainspring, mainstay, key and anchor. Learn more. Cornerstone definition, a stone uniting two masonry walls at an intersection. Usage: the whole argument rested on â¦ What is the meaning of cornerstone? Synonyms for 'cornerstone': feature, priority, element, basis, concern, key, essence, core, staple, burning issue/question, the ABC of something Find more similar words at â¦ Find more ways to say cornerstone, along with related words, antonyms and example phrases at Thesaurus.com, the world's most trusted free thesaurus. 1. a stone at the outer corner of two intersecting masonry walls 2. a stone in the exterior of a large and important building; usually carved with a date and laid with appropriate ceremonies 3. the fundamental assumptions from which something is begun or developed or calculated or explained "the whole argument â¦ What is the definition of cornerstone? Antonyms for cornerstone. Definition: the fundamental assumptions from which something is begun or developed or calculated or explained. See more. What are synonyms for cornerstone? How do you use cornerstone in a sentence? Another word for linchpin. Synonyms (Other Words) for Cornerstone & Antonyms (Opposite Meaning) for Cornerstone. Cornerstone. cornerstone definition: 1. a stone in a corner of a building, especially one with the date when the building was made orâ¦. Synonyms for cornerstone in Free Thesaurus. cornerstone (n.).