The crossword solution for the term 'Good Name for an Optimist' is 'Rosie' (5 letters). Rosie is a popular name that has been used since the Middle Ages. It is derived from the Latin word 'ROSA' which means rose, and is often associated with beauty and optimism. Rosie is also a popular nickname for people with the name Rosemary, which is derived from the Latin words 'ros' and 'marinus' meaning 'dew of the sea'. Therefore, Rosie is an appropriate name for an optimist as it is associated with beauty, hope, and joy.