/ˈäbt(y)əˌrātər/
Noun, pl. obturators
1. (Surgery) An object used to obstruct a hole, such as a fissure of the palate. (wiktionary.org); an apparatus designed to close an unnatural opening, as a fissure of the palate. (biology-online.org)
2. A prosthesis used to close an opening (as to close an opening of the hard palate in cases of cleft palate. (wordnetweb.princeton.edu)
Word origin: From Latin obtūrō “to stop, block up”.