Introse -um: directed inward, toward the body.
Intrusus: seemingly impressed with a sharp point.
Intumescent: enlarged; swollen: expanded.
Invaginate: when a tubular or vesicular part is turned inward or retracted within the body wall.
Invagination: a pouch or sac formed by an infolding or indrawing of the outer surface.
Investitus: unclothed: a surface without scales or hair.
Involucrate: = involute.
Involucrum alarum in Dermaptera a flap of the metanotum.
Involute: spirally rolled inwardly.
Involuti: butterflies whose larvae live in a folded leaf; Hesperidae.