An orangery or orangerie is a room or dedicated building, historically where orange and other fruit trees are protected during the winter, as a large form of greenhouse or conservatory. In the modern day an orangery could refer to either a conservatory or greenhouse built to house fruit trees, or a conservatory or greenhouse meant for another purpose.

An orange, also called sweet orange to distinguish it from the bitter orange, is the fruit of a tree in the family Rutaceae. Botanically, this is the hybrid Citrus × sinensis, between the pomelo and the mandarin orange. The chloroplast genome, and therefore the maternal line, is that of pomelo. The sweet orange has had its full genome sequenced.