cot British and Australian, American crib
noun [C] 
a small bed for a baby or young child with high bars round the sides so that the child cannot fall out 
The baby is fast asleep in his cot.
a cot blanket/quilt

Cot is also Am for camp bed. 
See at camp (tents/buildings).

(A) cot death is the sudden death of a baby while it is sleeping because of problems with breathing.