Retrocession: the going or moving backward.
Retrose: (sinuate), pointing backwards; (serrate) inversely serrated.
Retuse: ending in an obtuse sinus or broad, shallow notch, terminated by an obtuse hollow.
Reversed: turned in, an unusual or contrary direction, as upside down or inside out: said of wings when they are deflexed, the margin of secondaries projecting beyond those of primaries.
Reviviscence: coming back to life; awakening from hibernation.
Revolute: spirally rolled backward.
Rhabdites: the blade-like elements of the sting and ovipositor: a rod or bladelike process projecting from the epidermis.
Rhabdom: the rod lying in the axis of the retinula, below the crystalline cone of an eye.
Rhabdomere: the rod-like distal portion of a retinular cell.
Rhabdopoda: clasping organs of the 9th abdominal segment of male.