Definition of Downtonian in English:

Downtonian

Pronunciation /daʊnˈtəʊnɪən/

adjective

historical Geology
  • Designating a stratigraphic stage or series of rocks corresponding to the lowermost Devonian and (originally) the uppermost Silurian; of or relating this stage or series.

noun

historical Geology
  • Chiefly with the. The Downtonian stage; the series of rocks dating from this time.

Origin

Late 19th century. From Downton, the name of a civil parish in the extreme north of Herefordshire, where this stratigraphic stage is found + -ian.