ˈinˌmōst also chiefly Brit -_məst adjective
Etymology: Middle English inmast, inmost, alteration (influenced by mast, most most) of inmest, from Old English innemest, superl. of inne, adverb, in, inside, within, from in, inn, adverb, in — more at in
: deepest within : farthest from the surface or external part : innermost
one's inmost self — J.B.Noss