The Collaborative International Dictionary of English v.0.48:

buyout \buy"out\ n. (Business, Finance)
   the acquisition of ownership of a company by purchasing a
   controlling percentage of its stock.

   Syn: takeover.
        [WordNet 1.5] buy out

The Collaborative International Dictionary of English v.0.48:

buy out \buy out\, buy-out \buy-out\v.
   to take over ownership of; -- of corporations and companies.

   Syn: take over, buy up.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

buyout
    n 1: acquisition of a company by purchasing a controlling
         percentage of its stock