greenhouses

[pinkerton]

Why is a greenhouse called a greenhouse?

[alavahalf]

Perhaps it's a house for your greens..?

[Buenchico]

It's self-explanatory when you remember that 'green' is not only an adjective but a verb.

From the Concise Oxford Dictionary (1):
green: to become green, especially with verdure

From the Concise Oxford Dictionary (2):
verdure: greenness of vegetation.

So a 'greenhouse' is a house where vegetation becomes green.

Chris

[Quizmonster]

According to The Oxford English Dictionary, the 'bible' in such matters, it comes from the noun, green - meaning a plant as in 'eat up your greens' - rather than the verb. So, I don't really agree with Chris's suggestion and a greenhouse is simply a place where plants are grown.

[Quizmonster]

Sorry, I meant to add above that Alavahalf has got it right.