1. (

• unanticipated ,
• unforeseen ,
• unseen ,
• unlooked-for ,
• out_of_the_blue

) not anticipated; "unanticipated and disconcerting lines of development"- H.W.Glidden; "unforeseen circumstances"; "a virtue unlooked-for in people so full of energy"; "like a bolt out of the blue"; "unseen problems" ;

1. (

• unexpectedly ,
• out_of_the_blue

) in a way that was not expected; "her brother showed up at the wedding out of the blue" ;