'Greenhouse' definitions:

Definition of 'greenhouse'

(from WordNet)
adjective
Of or relating to or caused by the greenhouse effect; "greenhouse gases"
noun
A building with glass walls and roof; for the cultivation and exhibition of plants under controlled conditions [syn: greenhouse, nursery, glasshouse]

Definition of 'Greenhouse'

From: GCIDE
  • Greenhouse \Green"house`\, n. A house in which tender plants are cultivated and sheltered from the weather. [1913 Webster]