peaking /ˈpiːkɪŋ/noun 3adjective 1forms 3 noun3 •The act of something reaching a peak.The peaking of each of these hormone levels may occur at different times. •The act of something operating when something else is at a peak. •The act of generating extra electricity while demand for it is at a peak (e.g., at certain times of day, in very hot weather, in very cold weather).Currently their best stopgap for peaking in this region is a vast fleet of small diesel gensets, which many residents are furious about. adjective1 •peaky; sickly; pining formspeakings · more peaking · most peaking