Definition of retroclusion in US English:

retroclusion

noun

  • Dentistry. Malocclusion in which the teeth of the lower jaw are posterior to those of the upper. rare.

Origin

Late 19th century (in an earlier sense). From retro- + -clusion.

Pronunciation

retroclusion

/ˌrɛtrə(ʊ)ˈkluːʒn/