Meaning : Not anticipated.
Example :
Unanticipated and disconcerting lines of development.
Unforeseen circumstances.
A virtue unlooked-for in people so full of energy.
Like a bolt out of the blue.
Unseen problems.
Synonyms : unanticipated, unforeseen, unlooked-for, unseen
Meaning : In a way that was not expected.
Example :
Her brother showed up at the wedding out of the blue.
Synonyms : unexpectedly
Out of the blue meaning in Bengali (Bangla).