Synonyms: key, keystone, headstone
Definition: the central building block at the top of an arch or vault
Similar words: building block
Definition: a block of material used in construction work
Synonyms: lynchpin, mainstay, keystone, linchpin, backbone, anchor
Definition: a central cohesive source of support and stability
Usage: faith is his anchor; the keystone of campaign reform was the ban on soft money; he is the linchpin of this firm
Similar words: support
Definition: something providing immaterial assistance to a person or cause or interest
Usage: the policy found little public support; his faith was all the support he needed; the team enjoyed the support of their fans