Definition of plate-tectonicist in US English:

plate-tectonicist

noun

Geology
  • An expert in or student of plate tectonics; an advocate of the plate-tectonic theory.

Origin

1970s; earliest use found in Nature: a weekly journal of science. From plate-tectonic + -ist, after e.g. physicist.

Pronunciation

plate-tectonicist

/ˌpleɪttɛkˈtɒnɪsɪst/