Definition of oversteepened in English:

oversteepened

Pronunciation /ˌəʊvəˈstiːp(ə)nd/

adjective

Geography
  • Steepened further; especially (of a valley or slope) having a greater steepness than running water would have caused owing to the predominantly downward erosive action of a glacier.

Origin

Early 20th century. From over- + steepen + -ed.