zebra

noun

1. Any of three species of genus Equus: E. grevyi, E. quagga, or E. zebra, all with black and white stripes and native to Africa.

2. A referee.

3. An unlikely diagnosis, especially for symptoms probably caused by a common ailment. (Originates in the advice often given to medical students: "when you hear hoofbeats, think of horses, not zebras".)

4. A biracial person, specifically one born to a member of the Sub-Saharan African race and a Caucasian.

5. A fish, the zebra cichlid.

6. Any of various papilionid butterflies of the subgenus Paranticopsis of the genus Graphium, having black and white markings.