Nacreous: pearly: resembling mother of pearl := margaritaceous.
Nail: a tarsal claw: specifically the stout pointed claws in predatory Heteroptera = unguis.
Naked: not clothed: lacking vestiture: a pupa when not inclosed in a cocoon or other covering.
Nasal suture: =clypeal suture; q.v.
Nasus: anterior termination of the face in certain Hymenoptera: the clypeus or a modification of it: in Odonata, the upper portion of the clypeus = supra-clypeus = postclypeus.
Nasuti: that type of termite soldiers that have the head prolonged into a point.
Natatorial -ions: formed for swimming.
Navicular: boat-shaped = cymbiform.
Neanic: referring to the pupal stage.
Nearctic: temperate and arctic North America, including Greenland.