Osmosis the the phenomenon in which water flows
through a membrane (like a cell wall) from
the low solute side to the high solute side.
(Try putting one carrot in tap water
and the other in salt water.)
You have probably heard of
reverse osmosis, which
is a way of purifying water.
Salinophiles can get around the osmosis problem by using
chemistry to change the distributions of dissolved minerals
inside and outside of their cells. This can prevent dehydration of cells.