As a noun foothills
is plural of foothill.
As an adjective submontane is
located at the base of a mountain, or in the foothills of a mountain chain.
foothills
Noun
(head)
Usage notes
The plural form is often used collectively to refer to a region of foothills near the base of a mountain range.
submontane
English
Adjective
(-)
Located at the base of a mountain, or in the foothills of a mountain chain.
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