sub-aqueous (adjective) deep: extending very far, usually down
Sinonime: abysmal, abyssal,
below,
beneath, bottomless,
broad, buried, deep-seated,
distant, downreaching,
far, fathomless,
immersed, inmost,
low,
profound,
rooted, subaqueous, submarine, submerged, subterranean, sunk,
underground,
unfathomable,
wide, yawning
Antonime: shallow