1. (Science: botany) The fruit of a tree of the genus citrus (Citrus Aurantium). It is usually round, and consists of pulpy carpels, commonly ten in number, inclosed in a leathery rind, which is easily separable, and is reddish yellow when ripe.
There are numerous varieties of oranges; as, the bitter orange, which is supposed to be the original stock; the navel orange, which has the rudiment of a second orange imbedded in the top of the fruit; the blood orange, with a reddish juice; and the horned orange, in which the carpels are partly separated.
4. (Science: zoology) mock orange, any species of scale insects which infests orange trees; especially, the purple scale (Mytilaspis citricola), the long scale (Mytilaspis Gloveri), and the red scale (Aspidiotus Aurantii).
Origin: F.; cf. It. Arancia, arancio, LL. Arangia, Sp. Naranjia, Pg. Laranja; all fr. Ar. Naranj, Per. Naranj, narang; cf. Skr. Naranga orange tree. The o- in F. Orange is due to confusion with or gold, L. Aurum, because the orange resembles gold in colour.