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Latin: Pavo cristatus (Indian peafowl)
JP: 孔雀 kujaku
Peacock refers colloquially to peafowl in general, of which the peacock is the male and the peahen is the female. Indian peacocks famously feature an unmistakable elongated tail (known as a train) with an eye-spot pattern in iridescent green, blue and gold/bronze. Their head and neck are royal blue, with a spray of tuft-tipped feathers at the back of the head and white markings below and above the eye.
Peahens are brown for camouflage.
White peafowl are generally leucistic (rather than albinistic). Additionally, there are hundreds of domestically-bred color variations, including purple, bronze, opal, midnight, charcoal, jade, and taupe.
Besides the Indian peafowl Pavo cristatus, there are also the green or Java peafowl Pavo muticus and the relatively dull-plumaged Congo or African peafowl Afropavo congensis.
See also
This tag implicates bird (learn more).