a dangerous stretch of shoals at the entrance to the Strait of Dover : separated from the E coast of Kent by the Downs roadstead
shifting sands
If you refer to the shifting sands of a situation, you mean that it changes so often that it is difficult to deal with.
oil sand
a sandstone impregnated with hydrocarbons , esp such deposits in Alberta , Canada
tar sand
a sandstone in which hydrocarbons have been trapped ; the lighter compounds evaporate , leaving a residue of asphalt in the rock pores
foundry sand
silica-based sand mixed with clay , oil, etc, to improve its cohesive strength, used in moulding
the sands are running out
there is not much time left before death or the end
bunker
A bunker is a place, usually underground, that has been built with strong walls to protect it against heavy gunfire and bombing .
acervulus
a small, asexual spore-producing structure produced by certain parasitic fungi on a host plant
freshwater shrimp
any of various chiefly marine decapod crustaceans of the genus Crangon and related genera, having a slender flattened body with a long tail and a single pair of pincers
sand shrimp
any of various chiefly marine decapod crustaceans of the genus Crangon and related genera, having a slender flattened body with a long tail and a single pair of pincers
shrimp
Shrimps are small shellfish with long tails and many legs .