Definition of "Nest" :

noun: a kind of gun emplacement

"A machine-gun nest."

noun: furniture pieces made to fit close together

noun: a gang of people (criminals or spies or terrorists) assembled in one locality

"A nest of thieves."

noun: a cosy or secluded retreat

noun: a structure in which animals lay eggs or give birth to their young

verb: gather nests

verb: move or arrange oneself in a comfortable and cozy position

verb: fit together or fit inside

"Nested bowls."

verb: inhabit a nest, usually after building

"Birds are nesting outside my window every Spring."