KEYSTONE /ˈkiː.stəʊn/ Scrabble 15 Words With Friends 15 Definition noun a central cohesive source of support and stability. — synonyms: anchor, mainstay, backbone, linchpin, lynchpin noun the central building block at the top of an arch or vault. — synonyms: key, headstone Anagrams of KEYSTONE keynotes See all 147 words you can make from KEYSTONE → 8-letter words Words starting with K Words ending with E ← Unscramble different letters