"Foreshadowing" may be the term you're thinking of. But, if so, I don't think it just refers to the climax; but can refer to any significant incident in the plot.
geofbob is right. In his book 'Story', Robert McKee identifies three key parts to any tale - inciting incident, crisis and resolution. The inciting incident is what leads inevitably to the crisis and thus the resolution. To make this satisfactory, foreshadowing is used, which gives the reader an anticipation of certain possibilities. As Geofbob says, it need not refer to an overall climax, but will normally be associated with a climax of some kind.