The crossword solution for the term 'Source of Steadiness' is 'BRACE'. A BRACE is a device used to provide support and stability to an object or structure. It is often used in construction to reinforce walls, beams, and other structures. Braces are also used in medical settings to support weakened joints and muscles. In everyday life, braces can be used to provide extra support and steadiness to furniture, appliances, and other objects.