greenhouse effect(The warming of the Earth's atmosphere caused by the increasing concentration of atmospheric gases, such as water vapour and carbon dioxide. These gases absorb radiation emitted by the Earth, thus slowing down the loss of radiant energy from the Earth back to space)
greenhouse gas(A collective expression for those components of the atmosphere that influence the greenhouse effect, namely carbon dioxide, methane, nitrous oxides, ozone, CFCs and water vapour, GHG)