·add. ·noun A peculiar mammal (Okapia johnostoni) closely related to the giraffe, discovered in the deep forests of Belgian Kongo in 1900. It is smaller than an ox, and somewhat like a giraffe, except that the neck is much shorter. Like the giraffe, it has no dewclaws. There is a small prominence on each frontal bone of the male. The color of the body is chiefly reddish chestnut, the cheeks are yellowish white, and the fore and hind legs above the knees and the haunches are striped with purplish black and cream color.