subacoustic

Etymology tree
Proto-Indo-European *upó
Proto-Italic *supo
Latin sub
Latin sub-der.
English sub-
Proto-Indo-European *h₂eḱ-
Proto-Indo-European *h₂ew-
Proto-Indo-European *-s
Proto-Indo-European *h₂ṓws
Proto-Indo-European *-yéti
Proto-Indo-European *h₂ḱh₂owsyéti
Proto-Hellenic *akóuhō
Ancient Greek ἀκούω (akoúō)
Proto-Indo-European *-kos
Ancient Greek -κός (-kós)
Ancient Greek -ῐκός (-ĭkós)
Ancient Greek ᾰ̓κουστῐκός (ăkoustĭkós)bor.
Medieval Latin acousticusbor.
English acoustic
English subacoustic
From sub- + acoustic.