subjacent
adjective
sub·ja·cent ˌsəb-ˈjā-sᵊnt 
: lying under or below
also : lower than though not directly below
hills and subjacent valleys
subjacently adverb
Word History
Etymology
Latin subjacent-, subjacens, present participle of subjacēre to lie under, from sub- + jacēre to lie — more at adjacent
First Known Use
1583, in the meaning defined above
Medical Definition
subjacent
adjective
sub·ja·cent səb-ˈjās-ᵊnt
: lying immediately under or below
subjacent tissue
severe bone loss subjacent to gingival inflammation