Answer: undersea

AnswerCrossword Clue
UNDERSEA

Like Cousteau's world

UNDERSEA

Like a Cousteau exploration

UNDERSEA

Like a herring's habitat

UNDERSEA
Like Atlantis, according to legend
UNDERSEA
Like submarine warfare
UNDERSEAPhone cable site
UNDERSEASubmarine
UNDERSEALike some volcanoes
UNDERSEADescribing Nemo's adventure.
UNDERSEASubmarine's habitat.
UNDERSEAFrogman's milieu.
UNDERSEAThe Nautilus' realm.
UNDERSEAIn the depths.
UNDERSEASubmarine.
UNDERSEASpear-fishing milieu.
UNDERSEALike the milieu of the chambered nautilus
UNDERSEABeneath the Baltic's surface
UNDERSEALike the Titanic
UNDERSEALike Cousteau's work
UNDERSEALike scuba diving
UNDERSEASubaquatic
UNDERSEALike much plant life
UNDERSEALike some phone cables
UNDERSEALike Davy Jones's locker