Webster’s Revised Unabridged Dictionary · 1913
Invaginate
In·vag′i·nate, v. t. To insert as in a sheath; to produce intussusception in.
In·vag′i·nate, In·vag′i·na′ted, a. (Biol.) (a) Sheathed. (b) Having one portion of a hollow organ drawn back within another portion.