oversteepened
/ˌəʊvəˈstiːp(ə)nd/Chiefly Physical Geography
adjective
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. Compare overdeepened and slightly later oversteepening.