causing an emotional disturbance; "his disconcerting habit of greeting friends ferociously and strangers charmingly"- Herb Caen; "an upsetting experience"
so remarkably different or sudden as to cause momentary shock or alarm; "Sydney's startling new Opera House"; "startling news"; "startling earthquake shocks"
an obstruction that stands in the way (and must be removed or surmounted or circumvented)
something immaterial that stands in the way and must be circumvented or surmounted; "lack of imagination is an obstacle to one's advancement"; "the poverty of a district is an obstacle to good education"; "the filibuster was a major obstruction to the success of their plan"
(law) a formal notice filed with a court or officer to suspend a proceeding until filer is given a hearing; "a caveat filed against the probate of a will"