(n): a protective covering (as for a knife or sword)
(n): baby bed with high sides made of slats
(n): a small bed for babies; enclosed by sides to prevent the baby from falling
(n): a small bed that folds up for storage or transport
(n): a piece of furniture that provides a place to sleep
Also see here for a map of the cot/caught merger in the US.
This word, as contrasted with caught, is somewhat famous among linguists. See here for the story.