rhynchokinesis
/ˌrɪŋkə(ʊ)kɪˈniːsɪs/ /ˌrɪŋkə(ʊ)kʌɪˈniːsɪs/Zoology
noun
A form of upper jaw mobility, found in some birds, in which the terminal part of the upper jaw may be raised or lowered independently of the rest of it by the bending of the nasal or premaxillary bones.
Origin
1960s. From rhyncho- + kinesis, after rhynchokinetic.