A slotting tool body includes a disc-like cutter portion including opposing forward and rearward cutter portion side surfaces and a cutter portion peripheral surface extending therebetween and a shank portion projecting rearwardly from the rearward cutter portion side surface. The cutter portion includes a number N of angularly spaced apart clamping portions, each having a peripherally disposed insert receiving slot. The cutter portion further includes a flexibility recess recessed in the forward cutter portion side surface and extending to each of the insert receiving slots. A cutting insert is releasably and resiliently clamped in each insert receiving slot to form a rotary slot cutting tool.