The orange—specifically, the sweet orange—is the citrus tree Citrus sinensis (syn. Citrus aurantium L.var. dulcis L., or Citrus aurantium Risso) and its fruit. The orange is a hybrid of ancient cultivated origin, possibly between pomelo (Citrus maxima) and tangerine (Citrus reticulata). It is a small floweringtree growing to about 10 m tall with evergreenleaves, which are arranged alternately, of ovate shape with crenulate margins and 4–10 cm long. The orange fruit is a hesperidium, a type of berry.
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