ಅರ್ಥ : In a way that was not expected.
ಉದಾಹರಣೆ :
Her brother showed up at the wedding out of the blue.
ಸಮಾನಾರ್ಥಕ : out of the blue
ಅರ್ಥ : Without advance planning.
ಉದಾಹರಣೆ :
They met accidentally.
ಸಮಾನಾರ್ಥಕ : accidentally, by chance, circumstantially
With intention. In an intentional manner.
He used that word intentionally.